Module netmiko.base_connection
Base connection class for netmiko
Handles SSH connection and methods that are generically applicable to different platforms (Cisco and non-Cisco).
Also defines methods that should generally be supported by child classes
Expand source code
"""
Base connection class for netmiko
Handles SSH connection and methods that are generically applicable to different
platforms (Cisco and non-Cisco).
Also defines methods that should generally be supported by child classes
"""
from typing import (
Optional,
Callable,
Any,
List,
Dict,
TypeVar,
cast,
Type,
Sequence,
Iterator,
TextIO,
Union,
Tuple,
Deque,
)
from typing import TYPE_CHECKING
from types import TracebackType
import io
import re
import socket
import telnetlib
import time
from collections import deque
from os import path
from pathlib import Path
from threading import Lock
import functools
import logging
import itertools
import paramiko
import serial
from tenacity import retry, stop_after_attempt, wait_exponential
import warnings
from netmiko import log
from netmiko.netmiko_globals import BACKSPACE_CHAR
from netmiko.exceptions import (
NetmikoTimeoutException,
NetmikoAuthenticationException,
ConfigInvalidException,
ReadException,
ReadTimeout,
)
from netmiko.channel import Channel, SSHChannel, TelnetChannel, SerialChannel
from netmiko.session_log import SessionLog
from netmiko.utilities import (
write_bytes,
check_serial_port,
structured_data_converter,
run_ttp_template,
select_cmd_verify,
calc_old_timeout,
)
from netmiko.utilities import m_exec_time # noqa
if TYPE_CHECKING:
from os import PathLike
# For decorators
F = TypeVar("F", bound=Callable[..., Any])
DELAY_FACTOR_DEPR_SIMPLE_MSG = """\n
Netmiko 4.x and later has deprecated the use of delay_factor and/or
max_loops in this context. You should remove any use of delay_factor=x
from this method call.\n"""
# Logging filter for #2597
class SecretsFilter(logging.Filter):
def __init__(self, no_log: Optional[Dict[Any, str]] = None) -> None:
self.no_log = no_log
def filter(self, record: logging.LogRecord) -> bool:
"""Removes secrets (no_log) from messages"""
if self.no_log:
for hidden_data in self.no_log.values():
record.msg = record.msg.replace(hidden_data, "********")
return True
def lock_channel(func: F) -> F:
@functools.wraps(func)
def wrapper_decorator(self: "BaseConnection", *args: Any, **kwargs: Any) -> Any:
self._lock_netmiko_session()
try:
return_val = func(self, *args, **kwargs)
finally:
# Always unlock the channel, even on exception.
self._unlock_netmiko_session()
return return_val
return cast(F, wrapper_decorator)
def log_writes(func: F) -> F:
"""Handle both session_log and log of writes."""
@functools.wraps(func)
def wrapper_decorator(self: "BaseConnection", out_data: str) -> None:
func(self, out_data)
try:
log.debug(
"write_channel: {}".format(
str(write_bytes(out_data, encoding=self.encoding))
)
)
if self.session_log:
if self.session_log.fin or self.session_log.record_writes:
self.session_log.write(out_data)
except UnicodeDecodeError:
# Don't log non-ASCII characters; this is null characters and telnet IAC (PY2)
pass
return None
return cast(F, wrapper_decorator)
class BaseConnection:
"""
Defines vendor independent methods.
Otherwise method left as a stub method.
"""
def __init__(
self,
ip: str = "",
host: str = "",
username: str = "",
password: Optional[str] = None,
secret: str = "",
port: Optional[int] = None,
device_type: str = "",
verbose: bool = False,
global_delay_factor: float = 1.0,
global_cmd_verify: Optional[bool] = None,
use_keys: bool = False,
key_file: Optional[str] = None,
pkey: Optional[paramiko.PKey] = None,
passphrase: Optional[str] = None,
disabled_algorithms: Optional[Dict[str, Any]] = None,
allow_agent: bool = False,
ssh_strict: bool = False,
system_host_keys: bool = False,
alt_host_keys: bool = False,
alt_key_file: str = "",
ssh_config_file: Optional[str] = None,
#
# Connect timeouts
# ssh-connect --> TCP conn (conn_timeout) --> SSH-banner (banner_timeout)
# --> Auth response (auth_timeout)
conn_timeout: int = 10,
# Timeout to wait for authentication response
auth_timeout: Optional[int] = None,
banner_timeout: int = 15, # Timeout to wait for the banner to be presented
# Other timeouts
blocking_timeout: int = 20, # Read blocking timeout
timeout: int = 100, # TCP connect timeout | overloaded to read-loop timeout
session_timeout: int = 60, # Used for locking/sharing the connection
read_timeout_override: Optional[float] = None,
keepalive: int = 0,
default_enter: Optional[str] = None,
response_return: Optional[str] = None,
serial_settings: Optional[Dict[str, Any]] = None,
fast_cli: bool = True,
_legacy_mode: bool = False,
session_log: Optional[SessionLog] = None,
session_log_record_writes: bool = False,
session_log_file_mode: str = "write",
allow_auto_change: bool = False,
encoding: str = "utf-8",
sock: Optional[socket.socket] = None,
auto_connect: bool = True,
delay_factor_compat: bool = False,
) -> None:
"""
Initialize attributes for establishing connection to target device.
:param ip: IP address of target device. Not required if `host` is
provided.
:param host: Hostname of target device. Not required if `ip` is
provided.
:param username: Username to authenticate against target device if
required.
:param password: Password to authenticate against target device if
required.
:param secret: The enable password if target device requires one.
:param port: The destination port used to connect to the target
device.
:param device_type: Class selection based on device type.
:param verbose: Enable additional messages to standard output.
:param global_delay_factor: Multiplication factor affecting Netmiko delays (default: 1).
:param use_keys: Connect to target device using SSH keys.
:param key_file: Filename path of the SSH key file to use.
:param pkey: SSH key object to use.
:param passphrase: Passphrase to use for encrypted key; password will be used for key
decryption if not specified.
:param disabled_algorithms: Dictionary of SSH algorithms to disable. Refer to the Paramiko
documentation for a description of the expected format.
:param allow_agent: Enable use of SSH key-agent.
:param ssh_strict: Automatically reject unknown SSH host keys (default: False, which
means unknown SSH host keys will be accepted).
:param system_host_keys: Load host keys from the users known_hosts file.
:param alt_host_keys: If `True` host keys will be loaded from the file specified in
alt_key_file.
:param alt_key_file: SSH host key file to use (if alt_host_keys=True).
:param ssh_config_file: File name of OpenSSH configuration file.
:param timeout: Connection timeout.
:param session_timeout: Set a timeout for parallel requests.
:param auth_timeout: Set a timeout (in seconds) to wait for an authentication response.
:param banner_timeout: Set a timeout to wait for the SSH banner (pass to Paramiko).
:param keepalive: Send SSH keepalive packets at a specific interval, in seconds.
Currently defaults to 0, for backwards compatibility (it will not attempt
to keep the connection alive).
:param default_enter: Character(s) to send to correspond to enter key (default: \n).
:param response_return: Character(s) to use in normalized return data to represent
enter key (default: \n)
:param fast_cli: Provide a way to optimize for performance. Converts select_delay_factor
to select smallest of global and specific. Sets default global_delay_factor to .1
(default: True)
:param session_log: File path or BufferedIOBase subclass object to write the session log to.
:param session_log_record_writes: The session log generally only records channel reads due
to eliminate command duplication due to command echo. You can enable this if you
want to record both channel reads and channel writes in the log (default: False).
:param session_log_file_mode: "write" or "append" for session_log file mode
(default: "write")
:param allow_auto_change: Allow automatic configuration changes for terminal settings.
(default: False)
:param encoding: Encoding to be used when writing bytes to the output channel.
(default: ascii)
:param sock: An open socket or socket-like object (such as a `.Channel`) to use for
communication to the target host (default: None).
:param global_cmd_verify: Control whether command echo verification is enabled or disabled
(default: None). Global attribute takes precedence over function `cmd_verify`
argument. Value of `None` indicates to use function `cmd_verify` argument.
:param auto_connect: Control whether Netmiko automatically establishes the connection as
part of the object creation (default: True).
:param delay_factor_compat: Set send_command and send_command_timing back to using Netmiko
3.x behavior for delay_factor/global_delay_factor/max_loops. This argument will be
eliminated in Netmiko 5.x (default: False).
"""
self.remote_conn: Union[
None, telnetlib.Telnet, paramiko.Channel, serial.Serial
] = None
# Does the platform support a configuration mode
self._config_mode = True
self._read_buffer = ""
self.delay_factor_compat = delay_factor_compat
self.TELNET_RETURN = "\r\n"
if default_enter is None:
if "telnet" not in device_type:
self.RETURN = "\n"
else:
self.RETURN = self.TELNET_RETURN
else:
self.RETURN = default_enter
# Line Separator in response lines
self.RESPONSE_RETURN = "\n" if response_return is None else response_return
if ip:
self.host = ip.strip()
elif host:
self.host = host.strip()
if not ip and not host and "serial" not in device_type:
raise ValueError("Either ip or host must be set")
if port is None:
if "telnet" in device_type:
port = 23
else:
port = 22
self.port = int(port)
self.username = username
self.password = password
self.secret = secret
self.device_type = device_type
self.ansi_escape_codes = False
self.verbose = verbose
self.auth_timeout = auth_timeout
self.banner_timeout = banner_timeout
self.blocking_timeout = blocking_timeout
self.conn_timeout = conn_timeout
self.session_timeout = session_timeout
self.timeout = timeout
self.read_timeout_override = read_timeout_override
self.keepalive = keepalive
self.allow_auto_change = allow_auto_change
self.encoding = encoding
self.sock = sock
self.fast_cli = fast_cli
self._legacy_mode = _legacy_mode
self.global_delay_factor = global_delay_factor
self.global_cmd_verify = global_cmd_verify
if self.fast_cli and self.global_delay_factor == 1:
self.global_delay_factor = 0.1
self.session_log = None
self._session_log_close = False
# prevent logging secret data
no_log = {}
if self.password:
no_log["password"] = self.password
if self.secret:
no_log["secret"] = self.secret
log.addFilter(SecretsFilter(no_log=no_log))
# Netmiko will close the session_log if we open the file
if session_log is not None:
if isinstance(session_log, str):
# If session_log is a string, open a file corresponding to string name.
self.session_log = SessionLog(
file_name=session_log,
file_mode=session_log_file_mode,
no_log=no_log,
record_writes=session_log_record_writes,
)
self.session_log.open()
elif isinstance(session_log, io.BufferedIOBase):
# In-memory buffer or an already open file handle
self.session_log = SessionLog(
buffered_io=session_log,
no_log=no_log,
record_writes=session_log_record_writes,
)
else:
raise ValueError(
"session_log must be a path to a file, a file handle, "
"or a BufferedIOBase subclass."
)
# Default values
self.serial_settings = {
"port": "COM1",
"baudrate": 9600,
"bytesize": serial.EIGHTBITS,
"parity": serial.PARITY_NONE,
"stopbits": serial.STOPBITS_ONE,
}
if serial_settings is None:
serial_settings = {}
self.serial_settings.update(serial_settings)
if "serial" in device_type:
self.host = "serial"
comm_port = self.serial_settings.pop("port")
# Get the proper comm port reference if a name was enterred
comm_port = check_serial_port(comm_port)
self.serial_settings.update({"port": comm_port})
# set in set_base_prompt method
self.base_prompt = ""
self._session_locker = Lock()
# determine if telnet or SSH
if "_telnet" in device_type:
self.protocol = "telnet"
self.password = password or ""
elif "_serial" in device_type:
self.protocol = "serial"
self.password = password or ""
else:
self.protocol = "ssh"
self.key_policy: paramiko.client.MissingHostKeyPolicy
if not ssh_strict:
self.key_policy = paramiko.AutoAddPolicy()
else:
self.key_policy = paramiko.RejectPolicy()
# Options for SSH host_keys
self.use_keys = use_keys
self.key_file = (
path.abspath(path.expanduser(key_file)) if key_file else None
)
if self.use_keys is True:
self._key_check()
self.pkey = pkey
self.passphrase = passphrase
self.allow_agent = allow_agent
self.system_host_keys = system_host_keys
self.alt_host_keys = alt_host_keys
self.alt_key_file = alt_key_file
self.disabled_algorithms = disabled_algorithms or {}
# For SSH proxy support
self.ssh_config_file = ssh_config_file
# Establish the remote connection
if auto_connect:
self._open()
def _open(self) -> None:
"""Decouple connection creation from __init__ for mocking."""
self._modify_connection_params()
self.establish_connection()
self._try_session_preparation()
def __enter__(self) -> "BaseConnection":
"""Establish a session using a Context Manager."""
return self
def __exit__(
self,
exc_type: Optional[Type[BaseException]],
exc_value: Optional[BaseException],
traceback: Optional[TracebackType],
) -> None:
"""Gracefully close connection on Context Manager exit."""
self.disconnect()
def _modify_connection_params(self) -> None:
"""Modify connection parameters prior to SSH connection."""
pass
def _timeout_exceeded(self, start: float, msg: str = "Timeout exceeded!") -> bool:
"""Raise NetmikoTimeoutException if waiting too much in the serving queue.
:param start: Initial start time to see if session lock timeout has been exceeded
:type start: float (from time.time() call i.e. epoch time)
:param msg: Exception message if timeout was exceeded
:type msg: str
"""
if not start:
# Must provide a comparison time
return False
if time.time() - start > self.session_timeout:
# session_timeout exceeded
raise NetmikoTimeoutException(msg)
return False
def _lock_netmiko_session(self, start: Optional[float] = None) -> bool:
"""Try to acquire the Netmiko session lock. If not available, wait in the queue until
the channel is available again.
:param start: Initial start time to measure the session timeout
:type start: float (from time.time() call i.e. epoch time)
"""
if not start:
start = time.time()
# Wait here until the SSH channel lock is acquired or until session_timeout exceeded
while not self._session_locker.acquire(False) and not self._timeout_exceeded(
start, "The netmiko channel is not available!"
):
time.sleep(0.1)
return True
def _unlock_netmiko_session(self) -> None:
"""
Release the channel at the end of the task.
"""
if self._session_locker.locked():
self._session_locker.release()
def _autodetect_fs(self, cmd: str = "", pattern: str = "") -> str:
raise NotImplementedError
def _enter_shell(self) -> str:
raise NotImplementedError
def _return_cli(self) -> str:
raise NotImplementedError
def _key_check(self) -> bool:
"""Verify key_file exists."""
msg = f"""
use_keys has been set to True, but specified key_file does not exist:
use_keys: {self.use_keys}
key_file: {self.key_file}
"""
if self.key_file is None:
raise ValueError(msg)
my_key_file = Path(self.key_file)
if not my_key_file.is_file():
raise ValueError(msg)
return True
@lock_channel
@log_writes
def write_channel(self, out_data: str) -> None:
"""Generic method that will write data out the channel.
:param out_data: data to be written to the channel
:type out_data: str
"""
self.channel.write_channel(out_data)
def is_alive(self) -> bool:
"""Returns a boolean flag with the state of the connection."""
null = chr(0)
if self.remote_conn is None:
log.error("Connection is not initialised, is_alive returns False")
return False
if self.protocol == "telnet":
try:
# Try sending IAC + NOP (IAC is telnet way of sending command)
# IAC = Interpret as Command; it comes before the NOP.
log.debug("Sending IAC + NOP")
# Need to send multiple times to test connection
assert isinstance(self.remote_conn, telnetlib.Telnet)
telnet_socket = self.remote_conn.get_socket()
telnet_socket.sendall(telnetlib.IAC + telnetlib.NOP)
telnet_socket.sendall(telnetlib.IAC + telnetlib.NOP)
telnet_socket.sendall(telnetlib.IAC + telnetlib.NOP)
return True
except AttributeError:
return False
else:
# SSH
try:
# Try sending ASCII null byte to maintain the connection alive
log.debug("Sending the NULL byte")
self.write_channel(null)
assert isinstance(self.remote_conn, paramiko.Channel)
assert self.remote_conn.transport is not None
result = self.remote_conn.transport.is_active()
assert isinstance(result, bool)
return result
except (socket.error, EOFError):
log.error("Unable to send", exc_info=True)
# If unable to send, we can tell for sure that the connection is unusable
return False
return False
@lock_channel
def read_channel(self) -> str:
"""Generic handler that will read all the data from given channel."""
new_data = self.channel.read_channel()
new_data = self.normalize_linefeeds(new_data)
if self.ansi_escape_codes:
new_data = self.strip_ansi_escape_codes(new_data)
log.debug(f"read_channel: {new_data}")
if self.session_log:
self.session_log.write(new_data)
# If data had been previously saved to the buffer, the prepend it to output
# do post read_channel so session_log/log doesn't record buffered data twice
if self._read_buffer:
output = self._read_buffer + new_data
self._read_buffer = ""
else:
output = new_data
return output
def read_until_pattern(
self,
pattern: str = "",
read_timeout: float = 10.0,
re_flags: int = 0,
max_loops: Optional[int] = None,
) -> str:
"""Read channel until pattern is detected.
Will return string up to and including pattern.
Returns ReadTimeout if pattern not detected in read_timeout seconds.
:param pattern: Regular expression pattern used to identify that reading is done.
:param read_timeout: maximum time to wait looking for pattern. Will raise ReadTimeout.
A read_timeout value of 0 will cause the loop to never timeout (i.e. it will keep
reading indefinitely until pattern is detected.
:param re_flags: regex flags used in conjunction with pattern (defaults to no flags).
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
"""
if max_loops is not None:
msg = """\n
Netmiko 4.x has deprecated the use of max_loops with read_until_pattern.
You should convert all uses of max_loops over to read_timeout=x
where x is the total number of seconds to wait before timing out.\n"""
warnings.warn(msg, DeprecationWarning)
if self.read_timeout_override:
read_timeout = self.read_timeout_override
output = ""
loop_delay = 0.01
start_time = time.time()
# if read_timeout == 0 or 0.0 keep reading indefinitely
while (time.time() - start_time < read_timeout) or (not read_timeout):
output += self.read_channel()
if re.search(pattern, output, flags=re_flags):
results = re.split(pattern, output, maxsplit=1, flags=re_flags)
# The string matched by pattern must be retained in the output string.
# re.split will do this if capturing parenthesis are used.
if len(results) == 2:
# no capturing parenthesis, convert and try again.
pattern = f"({pattern})"
results = re.split(pattern, output, maxsplit=1, flags=re_flags)
if len(results) != 3:
# well, we tried
msg = f"""Unable to successfully split output based on pattern:
pattern={pattern}
output={repr(output)}
results={results}
"""
raise ReadException(msg)
# Process such that everything before and including pattern is return.
# Everything else is retained in the _read_buffer
output, match_str, buffer = results
output = output + match_str
if buffer:
self._read_buffer += buffer
log.debug(f"Pattern found: {pattern} {output}")
return output
time.sleep(loop_delay)
msg = f"""\n\nPattern not detected: {repr(pattern)} in output.
Things you might try to fix this:
1. Adjust the regex pattern to better identify the terminating string. Note, in
many situations the pattern is automatically based on the network device's prompt.
2. Increase the read_timeout to a larger value.
You can also look at the Netmiko session_log or debug log for more information.\n\n"""
raise ReadTimeout(msg)
def read_channel_timing(
self,
last_read: float = 2.0,
read_timeout: float = 120.0,
delay_factor: Optional[float] = None,
max_loops: Optional[int] = None,
) -> str:
"""Read data on the channel based on timing delays.
General pattern is keep reading until no new data is read.
Once no new data is read wait `last_read` amount of time (one last read).
As long as no new data, then return data.
`read_timeout` is an absolute timer for how long to keep reading (which presupposes
we are still getting new data).
Setting `read_timeout` to zero will cause read_channel_timing to never expire based
on an absolute timeout. It will only complete based on timeout based on their being
no new data.
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
"""
if delay_factor is not None or max_loops is not None:
warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning)
if self.read_timeout_override:
read_timeout = self.read_timeout_override
# Time to delay in each read loop
loop_delay = 0.1
channel_data = ""
start_time = time.time()
# Set read_timeout to 0 to never timeout
while (time.time() - start_time < read_timeout) or (not read_timeout):
time.sleep(loop_delay)
new_data = self.read_channel()
# gather new output
if new_data:
channel_data += new_data
# if we have some output, but nothing new, then do the last read
elif channel_data != "":
# Make sure really done (i.e. no new data)
time.sleep(last_read)
new_data = self.read_channel()
if not new_data:
break
else:
channel_data += new_data
else:
msg = f"""\n
read_channel_timing's absolute timer expired.
The network device was continually outputting data for longer than {read_timeout}
seconds.
If this is expected i.e. the command you are executing is continually emitting
data for a long period of time, then you can set 'read_timeout=x' seconds. If
you want Netmiko to keep reading indefinitely (i.e. to only stop when there is
no new data), then you can set 'read_timeout=0'.
You can look at the Netmiko session_log or debug log for more information.
"""
raise ReadTimeout(msg)
return channel_data
def read_until_prompt(
self,
read_timeout: float = 10.0,
read_entire_line: bool = False,
re_flags: int = 0,
max_loops: Optional[int] = None,
) -> str:
"""Read channel up to and including self.base_prompt."""
pattern = re.escape(self.base_prompt)
if read_entire_line:
pattern = f"{pattern}.*"
return self.read_until_pattern(
pattern=pattern,
re_flags=re_flags,
max_loops=max_loops,
read_timeout=read_timeout,
)
def read_until_prompt_or_pattern(
self,
pattern: str = "",
read_timeout: float = 10.0,
read_entire_line: bool = False,
re_flags: int = 0,
max_loops: Optional[int] = None,
) -> str:
"""Read until either self.base_prompt or pattern is detected."""
prompt_pattern = re.escape(self.base_prompt)
if read_entire_line:
prompt_pattern = f"{prompt_pattern}.*"
if pattern:
combined_pattern = r"(?:{}|{})".format(prompt_pattern, pattern)
else:
combined_pattern = prompt_pattern
return self.read_until_pattern(
pattern=combined_pattern,
re_flags=re_flags,
max_loops=max_loops,
read_timeout=read_timeout,
)
def serial_login(
self,
pri_prompt_terminator: str = r"#\s*$",
alt_prompt_terminator: str = r">\s*$",
username_pattern: str = r"(?:[Uu]ser:|sername|ogin)",
pwd_pattern: str = r"assword",
delay_factor: float = 1.0,
max_loops: int = 20,
) -> str:
return self.telnet_login(
pri_prompt_terminator,
alt_prompt_terminator,
username_pattern,
pwd_pattern,
delay_factor,
max_loops,
)
def telnet_login(
self,
pri_prompt_terminator: str = r"#\s*$",
alt_prompt_terminator: str = r">\s*$",
username_pattern: str = r"(?:user:|username|login|user name)",
pwd_pattern: str = r"assword",
delay_factor: float = 1.0,
max_loops: int = 20,
) -> str:
"""Telnet login. Can be username/password or just password.
:param pri_prompt_terminator: Primary trailing delimiter for identifying a device prompt
:param alt_prompt_terminator: Alternate trailing delimiter for identifying a device prompt
:param username_pattern: Pattern used to identify the username prompt
:param delay_factor: See __init__: global_delay_factor
:param max_loops: Controls the wait time in conjunction with the delay_factor
"""
delay_factor = self.select_delay_factor(delay_factor)
# Revert telnet_login back to old speeds/delays
if delay_factor < 1:
if not self._legacy_mode and self.fast_cli:
delay_factor = 1
time.sleep(1 * delay_factor)
output = ""
return_msg = ""
i = 1
while i <= max_loops:
try:
output = self.read_channel()
return_msg += output
# Search for username pattern / send username
if re.search(username_pattern, output, flags=re.I):
# Sometimes username/password must be terminated with "\r" and not "\r\n"
self.write_channel(self.username + "\r")
time.sleep(1 * delay_factor)
output = self.read_channel()
return_msg += output
# Search for password pattern / send password
if re.search(pwd_pattern, output, flags=re.I):
# Sometimes username/password must be terminated with "\r" and not "\r\n"
assert isinstance(self.password, str)
self.write_channel(self.password + "\r")
time.sleep(0.5 * delay_factor)
output = self.read_channel()
return_msg += output
if re.search(
pri_prompt_terminator, output, flags=re.M
) or re.search(alt_prompt_terminator, output, flags=re.M):
return return_msg
# Check if proper data received
if re.search(pri_prompt_terminator, output, flags=re.M) or re.search(
alt_prompt_terminator, output, flags=re.M
):
return return_msg
self.write_channel(self.TELNET_RETURN)
time.sleep(0.5 * delay_factor)
i += 1
except EOFError:
assert self.remote_conn is not None
self.remote_conn.close()
msg = f"Login failed: {self.host}"
raise NetmikoAuthenticationException(msg)
# Last try to see if we already logged in
self.write_channel(self.TELNET_RETURN)
time.sleep(0.5 * delay_factor)
output = self.read_channel()
return_msg += output
if re.search(pri_prompt_terminator, output, flags=re.M) or re.search(
alt_prompt_terminator, output, flags=re.M
):
return return_msg
msg = f"Login failed: {self.host}"
assert self.remote_conn is not None
self.remote_conn.close()
raise NetmikoAuthenticationException(msg)
def _try_session_preparation(self, force_data: bool = True) -> None:
"""
In case of an exception happening during `session_preparation()` Netmiko should
gracefully clean-up after itself. This might be challenging for library users
to do since they do not have a reference to the object. This is possibly related
to threads used in Paramiko.
"""
try:
# Netmiko needs there to be data for session_preparation to work.
if force_data:
self.write_channel(self.RETURN)
time.sleep(0.1)
self.session_preparation()
except Exception:
self.disconnect()
raise
def session_preparation(self) -> None:
"""
Prepare the session after the connection has been established
This method handles some differences that occur between various devices
early on in the session.
In general, it should include:
self._test_channel_read(pattern=r"some_pattern")
self.set_base_prompt()
self.set_terminal_width()
self.disable_paging()
"""
self._test_channel_read()
self.set_base_prompt()
self.set_terminal_width()
self.disable_paging()
def _use_ssh_config(self, dict_arg: Dict[str, Any]) -> Dict[str, Any]:
"""Update SSH connection parameters based on contents of SSH config file.
:param dict_arg: Dictionary of SSH connection parameters
"""
connect_dict = dict_arg.copy()
# Use SSHConfig to generate source content.
assert self.ssh_config_file is not None
full_path = path.abspath(path.expanduser(self.ssh_config_file))
source: Union[paramiko.config.SSHConfigDict, Dict[str, Any]]
if path.exists(full_path):
ssh_config_instance = paramiko.SSHConfig()
with io.open(full_path, "rt", encoding="utf-8") as f:
ssh_config_instance.parse(f)
source = ssh_config_instance.lookup(self.host)
else:
source = {}
# Keys get normalized to lower-case
proxy: Optional[paramiko.proxy.ProxyCommand]
if "proxycommand" in source:
proxy = paramiko.ProxyCommand(source["proxycommand"])
elif "proxyjump" in source:
hops = list(reversed(source["proxyjump"].split(",")))
if len(hops) > 1:
raise ValueError(
"ProxyJump with more than one proxy server is not supported."
)
port = source.get("port", self.port)
host = source.get("hostname", self.host)
# -F {full_path} forces the continued use of the same SSH config file
cmd = "ssh -F {} -W {}:{} {}".format(full_path, host, port, hops[0])
proxy = paramiko.ProxyCommand(cmd)
else:
proxy = None
# Only update 'hostname', 'sock', 'port', and 'username'
# For 'port' and 'username' only update if using object defaults
if connect_dict["port"] == 22:
connect_dict["port"] = int(source.get("port", self.port))
if connect_dict["username"] == "":
connect_dict["username"] = source.get("user", self.username)
if proxy:
connect_dict["sock"] = proxy
connect_dict["hostname"] = source.get("hostname", self.host)
return connect_dict
def _connect_params_dict(self) -> Dict[str, Any]:
"""Generate dictionary of Paramiko connection parameters."""
conn_dict = {
"hostname": self.host,
"port": self.port,
"username": self.username,
"password": self.password,
"look_for_keys": self.use_keys,
"allow_agent": self.allow_agent,
"key_filename": self.key_file,
"pkey": self.pkey,
"passphrase": self.passphrase,
"disabled_algorithms": self.disabled_algorithms,
"timeout": self.conn_timeout,
"auth_timeout": self.auth_timeout,
"banner_timeout": self.banner_timeout,
"sock": self.sock,
}
# Check if using SSH 'config' file mainly for SSH proxy support
if self.ssh_config_file:
conn_dict = self._use_ssh_config(conn_dict)
return conn_dict
def _sanitize_output(
self,
output: str,
strip_command: bool = False,
command_string: Optional[str] = None,
strip_prompt: bool = False,
) -> str:
"""Strip out command echo and trailing router prompt."""
if strip_command and command_string:
command_string = self.normalize_linefeeds(command_string)
output = self.strip_command(command_string, output)
if strip_prompt:
output = self.strip_prompt(output)
return output
def establish_connection(self, width: int = 511, height: int = 1000) -> None:
"""Establish SSH connection to the network device
Timeout will generate a NetmikoTimeoutException
Authentication failure will generate a NetmikoAuthenticationException
:param width: Specified width of the VT100 terminal window (default: 511)
:type width: int
:param height: Specified height of the VT100 terminal window (default: 1000)
:type height: int
"""
self.channel: Channel
if self.protocol == "telnet":
self.remote_conn = telnetlib.Telnet(
self.host, port=self.port, timeout=self.timeout
)
# Migrating communication to channel class
self.channel = TelnetChannel(conn=self.remote_conn, encoding=self.encoding)
self.telnet_login()
elif self.protocol == "serial":
self.remote_conn = serial.Serial(**self.serial_settings)
self.channel = SerialChannel(conn=self.remote_conn, encoding=self.encoding)
self.serial_login()
elif self.protocol == "ssh":
ssh_connect_params = self._connect_params_dict()
self.remote_conn_pre: Optional[paramiko.SSHClient]
self.remote_conn_pre = self._build_ssh_client()
# initiate SSH connection
try:
self.remote_conn_pre.connect(**ssh_connect_params)
except socket.error as conn_error:
self.paramiko_cleanup()
msg = f"""TCP connection to device failed.
Common causes of this problem are:
1. Incorrect hostname or IP address.
2. Wrong TCP port.
3. Intermediate firewall blocking access.
Device settings: {self.device_type} {self.host}:{self.port}
"""
# Handle DNS failures separately
if "Name or service not known" in str(conn_error):
msg = (
f"DNS failure--the hostname you provided was not resolvable "
f"in DNS: {self.host}:{self.port}"
)
msg = msg.lstrip()
raise NetmikoTimeoutException(msg)
except paramiko.ssh_exception.AuthenticationException as auth_err:
self.paramiko_cleanup()
msg = f"""Authentication to device failed.
Common causes of this problem are:
1. Invalid username and password
2. Incorrect SSH-key file
3. Connecting to the wrong device
Device settings: {self.device_type} {self.host}:{self.port}
"""
msg += self.RETURN + str(auth_err)
raise NetmikoAuthenticationException(msg)
except paramiko.ssh_exception.SSHException as e:
self.paramiko_cleanup()
if "No existing session" in str(e):
msg = (
"Paramiko: 'No existing session' error: "
"try increasing 'conn_timeout' to 15 seconds or larger."
)
raise NetmikoTimeoutException(msg)
else:
msg = f"""
A paramiko SSHException occurred during connection creation:
{str(e)}
"""
raise NetmikoTimeoutException(msg)
if self.verbose:
print(f"SSH connection established to {self.host}:{self.port}")
# Use invoke_shell to establish an 'interactive session'
self.remote_conn = self.remote_conn_pre.invoke_shell(
term="vt100", width=width, height=height
)
self.remote_conn.settimeout(self.blocking_timeout)
if self.keepalive:
assert isinstance(self.remote_conn.transport, paramiko.Transport)
self.remote_conn.transport.set_keepalive(self.keepalive)
# Migrating communication to channel class
self.channel = SSHChannel(conn=self.remote_conn, encoding=self.encoding)
self.special_login_handler()
if self.verbose:
print("Interactive SSH session established")
return None
def _test_channel_read(self, count: int = 40, pattern: str = "") -> str:
"""Try to read the channel (generally post login) verify you receive data back.
:param count: the number of times to check the channel for data
:param pattern: Regular expression pattern used to determine end of channel read
"""
def _increment_delay(
main_delay: float, increment: float = 1.1, maximum: int = 8
) -> float:
"""Increment sleep time to a maximum value."""
main_delay = main_delay * increment
if main_delay >= maximum:
main_delay = maximum
return main_delay
i = 0
delay_factor = self.select_delay_factor(delay_factor=0)
if pattern:
return self.read_until_pattern(pattern=pattern, read_timeout=20)
main_delay = delay_factor * 0.1
time.sleep(main_delay * 10)
new_data = ""
while i <= count:
new_data += self.read_channel_timing(read_timeout=20)
if new_data:
return new_data
self.write_channel(self.RETURN)
main_delay = _increment_delay(main_delay)
time.sleep(main_delay)
i += 1
raise NetmikoTimeoutException("Timed out waiting for data")
def _build_ssh_client(self) -> paramiko.SSHClient:
"""Prepare for Paramiko SSH connection."""
# Create instance of SSHClient object
remote_conn_pre = paramiko.SSHClient()
# Load host_keys for better SSH security
if self.system_host_keys:
remote_conn_pre.load_system_host_keys()
if self.alt_host_keys and path.isfile(self.alt_key_file):
remote_conn_pre.load_host_keys(self.alt_key_file)
# Default is to automatically add untrusted hosts (make sure appropriate for your env)
remote_conn_pre.set_missing_host_key_policy(self.key_policy)
return remote_conn_pre
def select_delay_factor(self, delay_factor: float) -> float:
"""
Choose the greater of delay_factor or self.global_delay_factor (default).
In fast_cli choose the lesser of delay_factor of self.global_delay_factor.
:param delay_factor: See __init__: global_delay_factor
:type delay_factor: int
"""
if self.fast_cli:
if delay_factor and delay_factor <= self.global_delay_factor:
return delay_factor
else:
return self.global_delay_factor
else:
if delay_factor >= self.global_delay_factor:
return delay_factor
else:
return self.global_delay_factor
def special_login_handler(self, delay_factor: float = 1.0) -> None:
"""Handler for devices like WLC, Extreme ERS that throw up characters prior to login."""
pass
def disable_paging(
self,
command: str = "terminal length 0",
delay_factor: Optional[float] = None,
cmd_verify: bool = True,
pattern: Optional[str] = None,
) -> str:
"""Disable paging default to a Cisco CLI method.
:param command: Device command to disable pagination of output
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
"""
if delay_factor is not None:
warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning)
command = self.normalize_cmd(command)
log.debug("In disable_paging")
log.debug(f"Command: {command}")
self.write_channel(command)
# Make sure you read until you detect the command echo (avoid getting out of sync)
if cmd_verify and self.global_cmd_verify is not False:
output = self.read_until_pattern(
pattern=re.escape(command.strip()), read_timeout=20
)
elif pattern:
output = self.read_until_pattern(pattern=pattern, read_timeout=20)
else:
output = self.read_until_prompt()
log.debug(f"{output}")
log.debug("Exiting disable_paging")
return output
def set_terminal_width(
self,
command: str = "",
delay_factor: Optional[float] = None,
cmd_verify: bool = False,
pattern: Optional[str] = None,
) -> str:
"""CLI terminals try to automatically adjust the line based on the width of the terminal.
This causes the output to get distorted when accessed programmatically.
Set terminal width to 511 which works on a broad set of devices.
:param command: Command string to send to the device
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
"""
if delay_factor is not None:
warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning)
if not command:
return ""
command = self.normalize_cmd(command)
self.write_channel(command)
# Avoid cmd_verify here as terminal width must be set before doing cmd_verify
if cmd_verify and self.global_cmd_verify is not False:
output = self.read_until_pattern(pattern=re.escape(command.strip()))
elif pattern:
output = self.read_until_pattern(pattern=pattern)
else:
output = self.read_until_prompt()
return output
# Retry by sleeping .33 and then double sleep until 5 attempts (.33, .66, 1.32, etc)
@retry(
wait=wait_exponential(multiplier=0.33, min=0, max=5),
stop=stop_after_attempt(5),
reraise=True,
)
def set_base_prompt(
self,
pri_prompt_terminator: str = "#",
alt_prompt_terminator: str = ">",
delay_factor: float = 1.0,
pattern: Optional[str] = None,
) -> str:
"""Sets self.base_prompt
Used as delimiter for stripping of trailing prompt in output.
Should be set to something that is general and applies in multiple contexts. For Cisco
devices this will be set to router hostname (i.e. prompt without > or #).
This will be set on entering user exec or privileged exec on Cisco, but not when
entering/exiting config mode.
:param pri_prompt_terminator: Primary trailing delimiter for identifying a device prompt
:param alt_prompt_terminator: Alternate trailing delimiter for identifying a device prompt
:param delay_factor: See __init__: global_delay_factor
:param pattern: Regular expression pattern to search for in find_prompt() call
"""
if pattern is None:
if pri_prompt_terminator and alt_prompt_terminator:
pri_term = re.escape(pri_prompt_terminator)
alt_term = re.escape(alt_prompt_terminator)
pattern = rf"({pri_term}|{alt_term})"
elif pri_prompt_terminator:
pattern = re.escape(pri_prompt_terminator)
elif alt_prompt_terminator:
pattern = re.escape(alt_prompt_terminator)
if pattern:
prompt = self.find_prompt(delay_factor=delay_factor, pattern=pattern)
else:
prompt = self.find_prompt(delay_factor=delay_factor)
if not prompt[-1] in (pri_prompt_terminator, alt_prompt_terminator):
raise ValueError(f"Router prompt not found: {repr(prompt)}")
# If all we have is the 'terminator' just use that :-(
if len(prompt) == 1:
self.base_prompt = prompt
else:
# Strip off trailing terminator
self.base_prompt = prompt[:-1]
return self.base_prompt
def find_prompt(
self, delay_factor: float = 1.0, pattern: Optional[str] = None
) -> str:
"""Finds the current network device prompt, last line only.
:param delay_factor: See __init__: global_delay_factor
:type delay_factor: int
:param pattern: Regular expression pattern to determine whether prompt is valid
"""
delay_factor = self.select_delay_factor(delay_factor)
sleep_time = delay_factor * 0.25
self.clear_buffer()
self.write_channel(self.RETURN)
if pattern:
prompt = self.read_until_pattern(pattern=pattern)
else:
# Initial read
time.sleep(sleep_time)
prompt = self.read_channel().strip()
count = 0
while count <= 12 and not prompt:
if not prompt:
self.write_channel(self.RETURN)
time.sleep(sleep_time)
prompt = self.read_channel().strip()
if sleep_time <= 3:
# Double the sleep_time when it is small
sleep_time *= 2
else:
sleep_time += 1
count += 1
# If multiple lines in the output take the last line
prompt = prompt.split(self.RESPONSE_RETURN)[-1]
prompt = prompt.strip()
self.clear_buffer()
if not prompt:
raise ValueError(f"Unable to find prompt: {prompt}")
log.debug(f"[find_prompt()]: prompt is {prompt}")
return prompt
def clear_buffer(
self,
backoff: bool = True,
backoff_max: float = 3.0,
delay_factor: Optional[float] = None,
) -> str:
"""Read any data available in the channel."""
if delay_factor is None:
delay_factor = self.global_delay_factor
sleep_time = 0.1 * delay_factor
output = ""
for _ in range(10):
time.sleep(sleep_time)
data = self.read_channel()
data = self.strip_ansi_escape_codes(data)
output += data
if not data:
break
# Double sleep time each time we detect data
log.debug("Clear buffer detects data in the channel")
if backoff:
sleep_time *= 2
sleep_time = backoff_max if sleep_time >= backoff_max else sleep_time
return output
def command_echo_read(self, cmd: str, read_timeout: float) -> str:
# Make sure you read until you detect the command echo (avoid getting out of sync)
new_data = self.read_until_pattern(
pattern=re.escape(cmd), read_timeout=read_timeout
)
# There can be echoed prompts that haven't been cleared before the cmd echo
# this can later mess up the trailing prompt pattern detection. Clear this out.
lines = new_data.split(cmd)
if len(lines) == 2:
# lines[-1] should realistically just be the null string
new_data = f"{cmd}{lines[-1]}"
else:
# cmd exists in the output multiple times? Just retain the original output
pass
return new_data
@select_cmd_verify
def send_command_timing(
self,
command_string: str,
last_read: float = 2.0,
read_timeout: float = 120.0,
delay_factor: Optional[float] = None,
max_loops: Optional[int] = None,
strip_prompt: bool = True,
strip_command: bool = True,
normalize: bool = True,
use_textfsm: bool = False,
textfsm_template: Optional[str] = None,
use_ttp: bool = False,
ttp_template: Optional[str] = None,
use_genie: bool = False,
cmd_verify: bool = False,
) -> Union[str, List[Any], Dict[str, Any]]:
"""Execute command_string on the SSH channel using a delay-based mechanism. Generally
used for show commands.
:param command_string: The command to be executed on the remote device.
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param strip_prompt: Remove the trailing router prompt from the output (default: True).
:param strip_command: Remove the echo of the command from the output (default: True).
:param normalize: Ensure the proper enter is sent at end of command (default: True).
:param use_textfsm: Process command output through TextFSM template (default: False).
:param textfsm_template: Name of template to parse output with; can be fully qualified
path, relative path, or name of file in current directory. (default: None).
:param use_ttp: Process command output through TTP template (default: False).
:param ttp_template: Name of template to parse output with; can be fully qualified
path, relative path, or name of file in current directory. (default: None).
:param use_genie: Process command output through PyATS/Genie parser (default: False).
:param cmd_verify: Verify command echo before proceeding (default: False).
"""
if delay_factor is not None or max_loops is not None:
warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning)
output = ""
new_data = ""
if normalize:
command_string = self.normalize_cmd(command_string)
self.write_channel(command_string)
cmd = command_string.strip()
if cmd and cmd_verify:
new_data = self.command_echo_read(cmd=cmd, read_timeout=10)
output += new_data
output += self.read_channel_timing(
last_read=last_read, read_timeout=read_timeout
)
output = self._sanitize_output(
output,
strip_command=strip_command,
command_string=command_string,
strip_prompt=strip_prompt,
)
return_data = structured_data_converter(
command=command_string,
raw_data=output,
platform=self.device_type,
use_textfsm=use_textfsm,
use_ttp=use_ttp,
use_genie=use_genie,
textfsm_template=textfsm_template,
ttp_template=ttp_template,
)
return return_data
def _send_command_timing_str(self, *args: Any, **kwargs: Any) -> str:
"""Wrapper for `send_command_timing` method that always returns a
string"""
output = self.send_command_timing(*args, **kwargs)
assert isinstance(output, str)
return output
def strip_prompt(self, a_string: str) -> str:
"""Strip the trailing router prompt from the output.
:param a_string: Returned string from device
:type a_string: str
"""
response_list = a_string.split(self.RESPONSE_RETURN)
last_line = response_list[-1]
if self.base_prompt in last_line:
return self.RESPONSE_RETURN.join(response_list[:-1])
else:
return a_string
def _first_line_handler(self, data: str, search_pattern: str) -> Tuple[str, bool]:
"""
In certain situations the first line will get repainted which causes a false
match on the terminating pattern.
Filter this out.
returns a tuple of (data, first_line_processed)
Where data is the original data potentially with the first line modified
and the first_line_processed is a flag indicating that we have handled the
first line.
"""
try:
# First line is the echo line containing the command. In certain situations
# it gets repainted and needs filtered
lines = data.split(self.RETURN)
first_line = lines[0]
if BACKSPACE_CHAR in first_line:
pattern = search_pattern + r".*$"
first_line = re.sub(pattern, repl="", string=first_line)
lines[0] = first_line
data = self.RETURN.join(lines)
return (data, True)
except IndexError:
return (data, False)
def _prompt_handler(self, auto_find_prompt: bool) -> str:
if auto_find_prompt:
try:
prompt = self.find_prompt()
except ValueError:
prompt = self.base_prompt
else:
prompt = self.base_prompt
return re.escape(prompt.strip())
@select_cmd_verify
def send_command(
self,
command_string: str,
expect_string: Optional[str] = None,
read_timeout: float = 10.0,
delay_factor: Optional[float] = None,
max_loops: Optional[int] = None,
auto_find_prompt: bool = True,
strip_prompt: bool = True,
strip_command: bool = True,
normalize: bool = True,
use_textfsm: bool = False,
textfsm_template: Optional[str] = None,
use_ttp: bool = False,
ttp_template: Optional[str] = None,
use_genie: bool = False,
cmd_verify: bool = True,
) -> Union[str, List[Any], Dict[str, Any]]:
"""Execute command_string on the SSH channel using a pattern-based mechanism. Generally
used for show commands. By default this method will keep waiting to receive data until the
network device prompt is detected. The current network device prompt will be determined
automatically.
:param command_string: The command to be executed on the remote device.
:param expect_string: Regular expression pattern to use for determining end of output.
If left blank will default to being based on router prompt.
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param strip_prompt: Remove the trailing router prompt from the output (default: True).
:param strip_command: Remove the echo of the command from the output (default: True).
:param normalize: Ensure the proper enter is sent at end of command (default: True).
:param use_textfsm: Process command output through TextFSM template (default: False).
:param textfsm_template: Name of template to parse output with; can be fully qualified
path, relative path, or name of file in current directory. (default: None).
:param use_ttp: Process command output through TTP template (default: False).
:param ttp_template: Name of template to parse output with; can be fully qualified
path, relative path, or name of file in current directory. (default: None).
:param use_genie: Process command output through PyATS/Genie parser (default: False).
:param cmd_verify: Verify command echo before proceeding (default: True).
"""
# Time to delay in each read loop
loop_delay = 0.025
if self.read_timeout_override:
read_timeout = self.read_timeout_override
if self.delay_factor_compat:
# For compatibility calculate the old equivalent read_timeout
# i.e. what it would have been in Netmiko 3.x
if delay_factor is None:
tmp_delay_factor = self.global_delay_factor
else:
tmp_delay_factor = self.select_delay_factor(delay_factor)
compat_timeout = calc_old_timeout(
max_loops=max_loops,
delay_factor=tmp_delay_factor,
loop_delay=0.2,
old_timeout=self.timeout,
)
msg = f"""\n
You have chosen to use Netmiko's delay_factor compatibility mode for
send_command. This will revert Netmiko to behave similarly to how it
did in Netmiko 3.x (i.e. to use delay_factor/global_delay_factor and
max_loops).
Using these parameters Netmiko has calculated an effective read_timeout
of {compat_timeout} and will set the read_timeout to this value.
Please convert your code to that new format i.e.:
net_connect.send_command(cmd, read_timeout={compat_timeout})
And then disable delay_factor_compat.
delay_factor_compat will be removed in Netmiko 5.x.\n"""
warnings.warn(msg, DeprecationWarning)
# Override the read_timeout with Netmiko 3.x way :-(
read_timeout = compat_timeout
else:
# No need for two deprecation messages so only display this if not using
# delay_factor_compat
if delay_factor is not None or max_loops is not None:
msg = """\n
Netmiko 4.x has deprecated the use of delay_factor/max_loops with
send_command. You should convert all uses of delay_factor and max_loops
over to read_timeout=x where x is the total number of seconds to wait
before timing out.\n"""
warnings.warn(msg, DeprecationWarning)
if expect_string is not None:
search_pattern = expect_string
else:
search_pattern = self._prompt_handler(auto_find_prompt)
if normalize:
command_string = self.normalize_cmd(command_string)
# Start the clock
start_time = time.time()
self.write_channel(command_string)
new_data = ""
cmd = command_string.strip()
if cmd and cmd_verify:
new_data = self.command_echo_read(cmd=cmd, read_timeout=10)
MAX_CHARS = 2_000_000
DEQUE_SIZE = 20
output = ""
# Check only the past N-reads. This is for the case where the output is
# very large (i.e. searching a very large string for a pattern a whole bunch of times)
past_n_reads: Deque[str] = deque(maxlen=DEQUE_SIZE)
first_line_processed = False
# Keep reading data until search_pattern is found or until read_timeout
while time.time() - start_time < read_timeout:
if new_data:
output += new_data
past_n_reads.append(new_data)
# Case where we haven't processed the first_line yet (there is a potential issue
# in the first line (in cases where the line is repainted).
if not first_line_processed:
output, first_line_processed = self._first_line_handler(
output, search_pattern
)
# Check if we have already found our pattern
if re.search(search_pattern, output):
break
else:
if len(output) <= MAX_CHARS:
if re.search(search_pattern, output):
break
else:
# Switch to deque mode if output is greater than MAX_CHARS
# Check if pattern is in the past n reads
if re.search(search_pattern, "".join(past_n_reads)):
break
time.sleep(loop_delay)
new_data = self.read_channel()
else: # nobreak
msg = f"""
Pattern not detected: {repr(search_pattern)} in output.
Things you might try to fix this:
1. Explicitly set your pattern using the expect_string argument.
2. Increase the read_timeout to a larger value.
You can also look at the Netmiko session_log or debug log for more information.
"""
raise ReadTimeout(msg)
output = self._sanitize_output(
output,
strip_command=strip_command,
command_string=command_string,
strip_prompt=strip_prompt,
)
return_val = structured_data_converter(
command=command_string,
raw_data=output,
platform=self.device_type,
use_textfsm=use_textfsm,
use_ttp=use_ttp,
use_genie=use_genie,
textfsm_template=textfsm_template,
ttp_template=ttp_template,
)
return return_val
def _send_command_str(self, *args: Any, **kwargs: Any) -> str:
"""Wrapper for `send_command` method that always returns a string"""
output = self.send_command(*args, **kwargs)
assert isinstance(output, str)
return output
def send_command_expect(
self, *args: Any, **kwargs: Any
) -> Union[str, List[Any], Dict[str, Any]]:
"""Support previous name of send_command method."""
return self.send_command(*args, **kwargs)
def _multiline_kwargs(self, **kwargs: Any) -> Dict[str, Any]:
strip_prompt = kwargs.get("strip_prompt", False)
kwargs["strip_prompt"] = strip_prompt
strip_command = kwargs.get("strip_command", False)
kwargs["strip_command"] = strip_command
return kwargs
def send_multiline(
self,
commands: Sequence[Union[str, List[str]]],
multiline: bool = True,
**kwargs: Any,
) -> str:
"""
commands should either be:
commands = [[cmd1, expect1], [cmd2, expect2], ...]]
Or
commands = [cmd1, cmd2, cmd3, ...]
Any expect_string that is a null-string will use pattern based on
device's prompt (unless expect_string argument is passed in via
kwargs.
"""
output = ""
if multiline:
kwargs = self._multiline_kwargs(**kwargs)
default_expect_string = kwargs.pop("expect_string", None)
if not default_expect_string:
auto_find_prompt = kwargs.get("auto_find_prompt", True)
default_expect_string = self._prompt_handler(auto_find_prompt)
if commands and isinstance(commands[0], str):
# If list of commands just send directly using default_expect_string (probably prompt)
for cmd in commands:
cmd = str(cmd)
output += self._send_command_str(
cmd, expect_string=default_expect_string, **kwargs
)
else:
# If list of lists, then first element is cmd and second element is expect_string
for cmd_item in commands:
assert not isinstance(cmd_item, str)
cmd, expect_string = cmd_item
if not expect_string:
expect_string = default_expect_string
output += self._send_command_str(
cmd, expect_string=expect_string, **kwargs
)
return output
def send_multiline_timing(
self, commands: Sequence[str], multiline: bool = True, **kwargs: Any
) -> str:
if multiline:
kwargs = self._multiline_kwargs(**kwargs)
output = ""
for cmd in commands:
cmd = str(cmd)
output += self._send_command_timing_str(cmd, **kwargs)
return output
@staticmethod
def strip_backspaces(output: str) -> str:
"""Strip any backspace characters out of the output.
:param output: Output obtained from a remote network device.
:type output: str
"""
backspace_char = "\x08"
return output.replace(backspace_char, "")
def strip_command(self, command_string: str, output: str) -> str:
"""
Strip command_string from output string
Cisco IOS adds backspaces into output for long commands (i.e. for commands that line wrap)
:param command_string: The command string sent to the device
:type command_string: str
:param output: The returned output as a result of the command string sent to the device
:type output: str
"""
backspace_char = "\x08"
# Check for line wrap (remove backspaces)
if backspace_char in output:
output = output.replace(backspace_char, "")
# Juniper has a weird case where the echoed command will be " \n"
# i.e. there is an extra space there.
cmd = command_string.strip()
if output.startswith(cmd):
output_lines = output.split(self.RESPONSE_RETURN)
new_output = output_lines[1:]
return self.RESPONSE_RETURN.join(new_output)
else:
# command_string isn't there; do nothing
return output
def normalize_linefeeds(self, a_string: str) -> str:
"""Convert `\r\r\n`,`\r\n`, `\n\r` to `\n.`
:param a_string: A string that may have non-normalized line feeds
i.e. output returned from device, or a device prompt
:type a_string: str
"""
newline = re.compile("(\r\r\r\n|\r\r\n|\r\n|\n\r)")
a_string = newline.sub(self.RESPONSE_RETURN, a_string)
if self.RESPONSE_RETURN == "\n":
# Convert any remaining \r to \n
return re.sub("\r", self.RESPONSE_RETURN, a_string)
else:
return a_string
def normalize_cmd(self, command: str) -> str:
"""Normalize CLI commands to have a single trailing newline.
:param command: Command that may require line feed to be normalized
:type command: str
"""
command = command.rstrip()
command += self.RETURN
return command
def check_enable_mode(self, check_string: str = "") -> bool:
"""Check if in enable mode. Return boolean.
:param check_string: Identification of privilege mode from device
:type check_string: str
"""
self.write_channel(self.RETURN)
output = self.read_until_prompt(read_entire_line=True)
return check_string in output
def enable(
self,
cmd: str = "",
pattern: str = "ssword",
enable_pattern: Optional[str] = None,
re_flags: int = re.IGNORECASE,
) -> str:
"""Enter enable mode.
:param cmd: Device command to enter enable mode
:param pattern: pattern to search for indicating device is waiting for password
:param enable_pattern: pattern indicating you have entered enable mode
:param re_flags: Regular expression flags used in conjunction with pattern
"""
output = ""
msg = (
"Failed to enter enable mode. Please ensure you pass "
"the 'secret' argument to ConnectHandler."
)
# Check if in enable mode
if not self.check_enable_mode():
# Send "enable" mode command
self.write_channel(self.normalize_cmd(cmd))
try:
# Read the command echo
end_data = ""
if self.global_cmd_verify is not False:
output += self.read_until_pattern(pattern=re.escape(cmd.strip()))
end_data = output.split(cmd.strip())[-1]
# Search for trailing prompt or password pattern
if pattern not in output and self.base_prompt not in end_data:
output += self.read_until_prompt_or_pattern(
pattern=pattern, re_flags=re_flags
)
# Send the "secret" in response to password pattern
if re.search(pattern, output):
self.write_channel(self.normalize_cmd(self.secret))
output += self.read_until_prompt()
# Search for terminating pattern if defined
if enable_pattern and not re.search(enable_pattern, output):
output += self.read_until_pattern(pattern=enable_pattern)
else:
if not self.check_enable_mode():
raise ValueError(msg)
except NetmikoTimeoutException:
raise ValueError(msg)
return output
def exit_enable_mode(self, exit_command: str = "") -> str:
"""Exit enable mode.
:param exit_command: Command that exits the session from privileged mode
:type exit_command: str
"""
output = ""
if self.check_enable_mode():
self.write_channel(self.normalize_cmd(exit_command))
output += self.read_until_prompt()
if self.check_enable_mode():
raise ValueError("Failed to exit enable mode.")
return output
def check_config_mode(
self, check_string: str = "", pattern: str = "", force_regex: bool = False
) -> bool:
"""Checks if the device is in configuration mode or not.
:param check_string: Identification of configuration mode from the device
:type check_string: str
:param pattern: Pattern to terminate reading of channel
:type pattern: str
"""
self.write_channel(self.RETURN)
# You can encounter an issue here (on router name changes) prefer delay-based solution
if not pattern:
output = self.read_channel_timing(read_timeout=10.0)
else:
output = self.read_until_pattern(pattern=pattern)
if force_regex:
return bool(re.search(check_string, output))
else:
return check_string in output
def config_mode(
self, config_command: str = "", pattern: str = "", re_flags: int = 0
) -> str:
"""Enter into config_mode.
:param config_command: Configuration command to send to the device
:type config_command: str
:param pattern: Pattern to terminate reading of channel
:type pattern: str
:param re_flags: Regular expression flags
:type re_flags: RegexFlag
"""
output = ""
if not self.check_config_mode():
self.write_channel(self.normalize_cmd(config_command))
# Make sure you read until you detect the command echo (avoid getting out of sync)
if self.global_cmd_verify is not False:
output += self.read_until_pattern(
pattern=re.escape(config_command.strip())
)
if pattern:
output += self.read_until_pattern(pattern=pattern, re_flags=re_flags)
else:
output += self.read_until_prompt(read_entire_line=True)
if not self.check_config_mode():
raise ValueError("Failed to enter configuration mode.")
return output
def exit_config_mode(self, exit_config: str = "", pattern: str = "") -> str:
"""Exit from configuration mode.
:param exit_config: Command to exit configuration mode
:type exit_config: str
:param pattern: Pattern to terminate reading of channel
:type pattern: str
"""
output = ""
if self.check_config_mode():
self.write_channel(self.normalize_cmd(exit_config))
# Make sure you read until you detect the command echo (avoid getting out of sync)
if self.global_cmd_verify is not False:
output += self.read_until_pattern(
pattern=re.escape(exit_config.strip())
)
if pattern:
output += self.read_until_pattern(pattern=pattern)
else:
output += self.read_until_prompt(read_entire_line=True)
if self.check_config_mode():
raise ValueError("Failed to exit configuration mode")
log.debug(f"exit_config_mode: {output}")
return output
def send_config_from_file(
self, config_file: Union[str, bytes, "PathLike[Any]"], **kwargs: Any
) -> str:
"""
Send configuration commands down the SSH channel from a file.
The file is processed line-by-line and each command is sent down the
SSH channel.
**kwargs are passed to send_config_set method.
:param config_file: Path to configuration file to be sent to the device
:param kwargs: params to be sent to send_config_set method
"""
with io.open(config_file, "rt", encoding="utf-8") as cfg_file:
commands = cfg_file.readlines()
return self.send_config_set(commands, **kwargs)
def send_config_set(
self,
config_commands: Union[str, Sequence[str], Iterator[str], TextIO, None] = None,
*,
exit_config_mode: bool = True,
read_timeout: Optional[float] = None,
delay_factor: Optional[float] = None,
max_loops: Optional[int] = None,
strip_prompt: bool = False,
strip_command: bool = False,
config_mode_command: Optional[str] = None,
cmd_verify: bool = True,
enter_config_mode: bool = True,
error_pattern: str = "",
terminator: str = r"#",
bypass_commands: Optional[str] = None,
) -> str:
"""
Send configuration commands down the SSH channel.
config_commands is an iterable containing all of the configuration commands.
The commands will be executed one after the other.
Automatically exits/enters configuration mode.
:param config_commands: Multiple configuration commands to be sent to the device
:param exit_config_mode: Determines whether or not to exit config mode after complete
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param strip_prompt: Determines whether or not to strip the prompt
:param strip_command: Determines whether or not to strip the command
:param read_timeout: Absolute timer to send to read_channel_timing. Should be rarely needed.
:param config_mode_command: The command to enter into config mode
:param cmd_verify: Whether or not to verify command echo for each command in config_set
:param enter_config_mode: Do you enter config mode before sending config commands
:param error_pattern: Regular expression pattern to detect config errors in the
output.
:param terminator: Regular expression pattern to use as an alternate terminator in certain
situations.
:param bypass_commands: Regular expression pattern indicating configuration commands
where cmd_verify is automatically disabled.
"""
if self.global_cmd_verify is not None:
cmd_verify = self.global_cmd_verify
if delay_factor is not None or max_loops is not None:
warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning)
# Calculate an equivalent read_timeout (if using old settings)
# Eliminate in Netmiko 5.x
if read_timeout is None:
max_loops = 150 if max_loops is None else max_loops
delay_factor = 1.0 if delay_factor is None else delay_factor
# If delay_factor has been set, then look at global_delay_factor
delay_factor = self.select_delay_factor(delay_factor)
read_timeout = calc_old_timeout(
max_loops=max_loops, delay_factor=delay_factor, loop_delay=0.1
)
if delay_factor is None:
delay_factor = self.select_delay_factor(0)
else:
delay_factor = self.select_delay_factor(delay_factor)
if read_timeout is None:
read_timeout = 15
else:
read_timeout = read_timeout
if config_commands is None:
return ""
elif isinstance(config_commands, str):
config_commands = (config_commands,)
if not hasattr(config_commands, "__iter__"):
raise ValueError("Invalid argument passed into send_config_set")
if bypass_commands is None:
# Commands where cmd_verify is automatically disabled reg-ex logical-or
bypass_commands = r"^banner .*$"
# Set bypass_commands="" to force no-bypass (usually for testing)
bypass_detected = False
if bypass_commands:
# Make a copy of the iterator
config_commands, config_commands_tmp = itertools.tee(config_commands, 2)
bypass_detected = any(
[True for cmd in config_commands_tmp if re.search(bypass_commands, cmd)]
)
if bypass_detected:
cmd_verify = False
# Send config commands
output = ""
if enter_config_mode:
if config_mode_command:
output += self.config_mode(config_mode_command)
else:
output += self.config_mode()
# Perform output gathering line-by-line (legacy way)
if self.fast_cli and self._legacy_mode and not error_pattern:
for cmd in config_commands:
self.write_channel(self.normalize_cmd(cmd))
# Gather output
output += self.read_channel_timing(read_timeout=read_timeout)
elif not cmd_verify:
for cmd in config_commands:
self.write_channel(self.normalize_cmd(cmd))
time.sleep(delay_factor * 0.05)
# Gather the output incrementally due to error_pattern requirements
if error_pattern:
output += self.read_channel_timing(read_timeout=read_timeout)
if re.search(error_pattern, output, flags=re.M):
msg = f"Invalid input detected at command: {cmd}"
raise ConfigInvalidException(msg)
# Standard output gathering (no error_pattern)
if not error_pattern:
output += self.read_channel_timing(read_timeout=read_timeout)
else:
for cmd in config_commands:
self.write_channel(self.normalize_cmd(cmd))
# Make sure command is echoed
output += self.read_until_pattern(pattern=re.escape(cmd.strip()))
# Read until next prompt or terminator (#); the .*$ forces read of entire line
pattern = f"(?:{re.escape(self.base_prompt)}.*$|{terminator}.*$)"
output += self.read_until_pattern(pattern=pattern, re_flags=re.M)
if error_pattern:
if re.search(error_pattern, output, flags=re.M):
msg = f"Invalid input detected at command: {cmd}"
raise ConfigInvalidException(msg)
if exit_config_mode:
output += self.exit_config_mode()
output = self._sanitize_output(output)
log.debug(f"{output}")
return output
def strip_ansi_escape_codes(self, string_buffer: str) -> str:
"""
Remove any ANSI (VT100) ESC codes from the output
http://en.wikipedia.org/wiki/ANSI_escape_code
Note: this does not capture ALL possible ANSI Escape Codes only the ones
I have encountered
Current codes that are filtered:
ESC = '\x1b' or chr(27)
ESC = is the escape character [^ in hex ('\x1b')
ESC[24;27H Position cursor
ESC[?25h Show the cursor
ESC[E Next line (HP does ESC-E)
ESC[K Erase line from cursor to the end of line
ESC[2K Erase entire line
ESC[1;24r Enable scrolling from start to row end
ESC[?6l Reset mode screen with options 640 x 200 monochrome (graphics)
ESC[?7l Disable line wrapping
ESC[2J Code erase display
ESC[00;32m Color Green (30 to 37 are different colors)
ESC[6n Get cursor position
ESC[1D Move cursor position leftward by x characters (1 in this case)
ESC[9999B Move cursor down N-lines (very large value is attempt to move to the
very bottom of the screen).
HP ProCurve and Cisco SG300 require this (possible others).
:param string_buffer: The string to be processed to remove ANSI escape codes
:type string_buffer: str
""" # noqa
code_position_cursor = chr(27) + r"\[\d+;\d+H"
code_show_cursor = chr(27) + r"\[\?25h"
code_next_line = chr(27) + r"E"
code_erase_line_end = chr(27) + r"\[K"
code_erase_line = chr(27) + r"\[2K"
code_erase_start_line = chr(27) + r"\[K"
code_enable_scroll = chr(27) + r"\[\d+;\d+r"
code_insert_line = chr(27) + r"\[(\d+)L"
code_carriage_return = chr(27) + r"\[1M"
code_disable_line_wrapping = chr(27) + r"\[\?7l"
code_reset_mode_screen_options = chr(27) + r"\[\?\d+l"
code_reset_graphics_mode = chr(27) + r"\[00m"
code_erase_display = chr(27) + r"\[2J"
code_erase_display_0 = chr(27) + r"\[J"
code_graphics_mode = chr(27) + r"\[\dm"
code_graphics_mode1 = chr(27) + r"\[\d\d;\d\dm"
code_graphics_mode2 = chr(27) + r"\[\d\d;\d\d;\d\dm"
code_graphics_mode3 = chr(27) + r"\[(3|4)\dm"
code_graphics_mode4 = chr(27) + r"\[(9|10)[0-7]m"
code_get_cursor_position = chr(27) + r"\[6n"
code_cursor_position = chr(27) + r"\[m"
code_attrs_off = chr(27) + r"\[0m"
code_reverse = chr(27) + r"\[7m"
code_cursor_left = chr(27) + r"\[\d+D"
code_cursor_forward = chr(27) + r"\[\d*C"
code_cursor_up = chr(27) + r"\[\d*A"
code_cursor_down = chr(27) + r"\[\d*B"
code_wrap_around = chr(27) + r"\[\?7h"
code_bracketed_paste_mode = chr(27) + r"\[\?2004h"
code_set = [
code_position_cursor,
code_show_cursor,
code_erase_line,
code_enable_scroll,
code_erase_start_line,
code_carriage_return,
code_disable_line_wrapping,
code_erase_line_end,
code_reset_mode_screen_options,
code_reset_graphics_mode,
code_erase_display,
code_graphics_mode,
code_graphics_mode1,
code_graphics_mode2,
code_graphics_mode3,
code_graphics_mode4,
code_get_cursor_position,
code_cursor_position,
code_erase_display,
code_erase_display_0,
code_attrs_off,
code_reverse,
code_cursor_left,
code_cursor_up,
code_cursor_down,
code_cursor_forward,
code_wrap_around,
code_bracketed_paste_mode,
]
output = string_buffer
for ansi_esc_code in code_set:
output = re.sub(ansi_esc_code, "", output)
# CODE_NEXT_LINE must substitute with return
output = re.sub(code_next_line, self.RETURN, output)
# Aruba and ProCurve switches can use code_insert_line for <enter>
insert_line_match = re.search(code_insert_line, output)
if insert_line_match:
# Substitute each insert_line with a new <enter>
count = int(insert_line_match.group(1))
output = re.sub(code_insert_line, count * self.RETURN, output)
return output
def cleanup(self, command: str = "") -> None:
"""Logout of the session on the network device plus any additional cleanup."""
pass
def paramiko_cleanup(self) -> None:
"""Cleanup Paramiko to try to gracefully handle SSH session ending."""
if self.remote_conn_pre is not None:
self.remote_conn_pre.close()
del self.remote_conn_pre
def disconnect(self) -> None:
"""Try to gracefully close the session."""
try:
self.cleanup()
except Exception:
# Keep going on cleanup process even if exceptions
pass
try:
if self.protocol == "ssh":
self.paramiko_cleanup()
elif self.protocol == "telnet":
assert isinstance(self.remote_conn, telnetlib.Telnet)
self.remote_conn.close()
elif self.protocol == "serial":
assert isinstance(self.remote_conn, serial.Serial)
self.remote_conn.close()
except Exception:
# There have been race conditions observed on disconnect.
pass
finally:
self.remote_conn_pre = None
self.remote_conn = None
if self.session_log:
self.session_log.close()
def commit(self) -> str:
"""Commit method for platforms that support this."""
raise AttributeError("Network device does not support 'commit()' method")
def save_config(
self, cmd: str = "", confirm: bool = False, confirm_response: str = ""
) -> str:
"""Not Implemented"""
raise NotImplementedError
def run_ttp(
self,
template: Union[str, bytes, "PathLike[Any]"],
res_kwargs: Optional[Dict[str, Any]] = None,
**kwargs: Any,
) -> Any:
"""
Run TTP template parsing by using input parameters to collect
devices output.
:param template: template content, OS path to template or reference
to template within TTP templates collection in
ttp://path/to/template.txt format
:param res_kwargs: ``**res_kwargs`` arguments to pass to TTP result method
:param kwargs: any other ``**kwargs`` to use for TTP object instantiation
TTP template must have inputs defined together with below parameters.
:param method: name of Netmiko connection object method to call, default ``send_command``
:param kwargs: Netmiko connection object method arguments
:param commands: list of commands to collect
Inputs' load could be of one of the supported formats and controlled by input's ``load``
attribute, supported values - python, yaml or json. For each input output collected
from device and parsed accordingly.
"""
if res_kwargs is None:
res_kwargs = {}
return run_ttp_template(
connection=self, template=template, res_kwargs=res_kwargs, **kwargs
)
class TelnetConnection(BaseConnection):
passFunctions
def lock_channel(func: ~F) ‑> ~F-
Expand source code
def lock_channel(func: F) -> F: @functools.wraps(func) def wrapper_decorator(self: "BaseConnection", *args: Any, **kwargs: Any) -> Any: self._lock_netmiko_session() try: return_val = func(self, *args, **kwargs) finally: # Always unlock the channel, even on exception. self._unlock_netmiko_session() return return_val return cast(F, wrapper_decorator) def log_writes(func: ~F) ‑> ~F-
Handle both session_log and log of writes.
Expand source code
def log_writes(func: F) -> F: """Handle both session_log and log of writes.""" @functools.wraps(func) def wrapper_decorator(self: "BaseConnection", out_data: str) -> None: func(self, out_data) try: log.debug( "write_channel: {}".format( str(write_bytes(out_data, encoding=self.encoding)) ) ) if self.session_log: if self.session_log.fin or self.session_log.record_writes: self.session_log.write(out_data) except UnicodeDecodeError: # Don't log non-ASCII characters; this is null characters and telnet IAC (PY2) pass return None return cast(F, wrapper_decorator)
Classes
class BaseConnection (ip: str = '', host: str = '', username: str = '', password: Optional[str] = None, secret: str = '', port: Optional[int] = None, device_type: str = '', verbose: bool = False, global_delay_factor: float = 1.0, global_cmd_verify: Optional[bool] = None, use_keys: bool = False, key_file: Optional[str] = None, pkey: Optional[paramiko.pkey.PKey] = None, passphrase: Optional[str] = None, disabled_algorithms: Optional[Dict[str, Any]] = None, allow_agent: bool = False, ssh_strict: bool = False, system_host_keys: bool = False, alt_host_keys: bool = False, alt_key_file: str = '', ssh_config_file: Optional[str] = None, conn_timeout: int = 10, auth_timeout: Optional[int] = None, banner_timeout: int = 15, blocking_timeout: int = 20, timeout: int = 100, session_timeout: int = 60, read_timeout_override: Optional[float] = None, keepalive: int = 0, default_enter: Optional[str] = None, response_return: Optional[str] = None, serial_settings: Optional[Dict[str, Any]] = None, fast_cli: bool = True, session_log: Optional[SessionLog] = None, session_log_record_writes: bool = False, session_log_file_mode: str = 'write', allow_auto_change: bool = False, encoding: str = 'utf-8', sock: Optional[socket.socket] = None, auto_connect: bool = True, delay_factor_compat: bool = False)-
Defines vendor independent methods.
Otherwise method left as a stub method.
Initialize attributes for establishing connection to target device. :param ip: IP address of target device. Not required if <code>host</code> is provided. :param host: Hostname of target device. Not required if <code>ip</code> is provided. :param username: Username to authenticate against target device if required. :param password: Password to authenticate against target device if required. :param secret: The enable password if target device requires one. :param port: The destination port used to connect to the target device. :param device_type: Class selection based on device type. :param verbose: Enable additional messages to standard output. :param global_delay_factor: Multiplication factor affecting Netmiko delays (default: 1). :param use_keys: Connect to target device using SSH keys. :param key_file: Filename path of the SSH key file to use. :param pkey: SSH key object to use. :param passphrase: Passphrase to use for encrypted key; password will be used for key decryption if not specified. :param disabled_algorithms: Dictionary of SSH algorithms to disable. Refer to the Paramiko documentation for a description of the expected format. :param allow_agent: Enable use of SSH key-agent. :param ssh_strict: Automatically reject unknown SSH host keys (default: False, which means unknown SSH host keys will be accepted). :param system_host_keys: Load host keys from the users known_hosts file. :param alt_host_keys: If <code>True</code> host keys will be loaded from the file specified in alt_key_file. :param alt_key_file: SSH host key file to use (if alt_host_keys=True). :param ssh_config_file: File name of OpenSSH configuration file. :param timeout: Connection timeout. :param session_timeout: Set a timeout for parallel requests. :param auth_timeout: Set a timeout (in seconds) to wait for an authentication response. :param banner_timeout: Set a timeout to wait for the SSH banner (pass to Paramiko). :param keepalive: Send SSH keepalive packets at a specific interval, in seconds. Currently defaults to 0, for backwards compatibility (it will not attempt to keep the connection alive). :param default_enter: Character(s) to send to correspond to enter key (default:).
:param response_return: Character(s) to use in normalized return data to represent enter key (default:)
:param fast_cli: Provide a way to optimize for performance. Converts select_delay_factor to select smallest of global and specific. Sets default global_delay_factor to .1 (default: True) :param session_log: File path or BufferedIOBase subclass object to write the session log to. :param session_log_record_writes: The session log generally only records channel reads due to eliminate command duplication due to command echo. You can enable this if you want to record both channel reads and channel writes in the log (default: False). :param session_log_file_mode: "write" or "append" for session_log file mode (default: "write") :param allow_auto_change: Allow automatic configuration changes for terminal settings. (default: False) :param encoding: Encoding to be used when writing bytes to the output channel. (default: ascii) :param sock: An open socket or socket-like object (such as a <code>.Channel</code>) to use for communication to the target host (default: None). :param global_cmd_verify: Control whether command echo verification is enabled or disabled (default: None). Global attribute takes precedence over function <code>cmd\_verify</code> argument. Value of <code>None</code> indicates to use function <code>cmd\_verify</code> argument. :param auto_connect: Control whether Netmiko automatically establishes the connection as part of the object creation (default: True). :param delay_factor_compat: Set send_command and send_command_timing back to using Netmiko 3.x behavior for delay_factor/global_delay_factor/max_loops. This argument will be eliminated in Netmiko 5.x (default: False).Expand source code
class BaseConnection: """ Defines vendor independent methods. Otherwise method left as a stub method. """ def __init__( self, ip: str = "", host: str = "", username: str = "", password: Optional[str] = None, secret: str = "", port: Optional[int] = None, device_type: str = "", verbose: bool = False, global_delay_factor: float = 1.0, global_cmd_verify: Optional[bool] = None, use_keys: bool = False, key_file: Optional[str] = None, pkey: Optional[paramiko.PKey] = None, passphrase: Optional[str] = None, disabled_algorithms: Optional[Dict[str, Any]] = None, allow_agent: bool = False, ssh_strict: bool = False, system_host_keys: bool = False, alt_host_keys: bool = False, alt_key_file: str = "", ssh_config_file: Optional[str] = None, # # Connect timeouts # ssh-connect --> TCP conn (conn_timeout) --> SSH-banner (banner_timeout) # --> Auth response (auth_timeout) conn_timeout: int = 10, # Timeout to wait for authentication response auth_timeout: Optional[int] = None, banner_timeout: int = 15, # Timeout to wait for the banner to be presented # Other timeouts blocking_timeout: int = 20, # Read blocking timeout timeout: int = 100, # TCP connect timeout | overloaded to read-loop timeout session_timeout: int = 60, # Used for locking/sharing the connection read_timeout_override: Optional[float] = None, keepalive: int = 0, default_enter: Optional[str] = None, response_return: Optional[str] = None, serial_settings: Optional[Dict[str, Any]] = None, fast_cli: bool = True, _legacy_mode: bool = False, session_log: Optional[SessionLog] = None, session_log_record_writes: bool = False, session_log_file_mode: str = "write", allow_auto_change: bool = False, encoding: str = "utf-8", sock: Optional[socket.socket] = None, auto_connect: bool = True, delay_factor_compat: bool = False, ) -> None: """ Initialize attributes for establishing connection to target device. :param ip: IP address of target device. Not required if `host` is provided. :param host: Hostname of target device. Not required if `ip` is provided. :param username: Username to authenticate against target device if required. :param password: Password to authenticate against target device if required. :param secret: The enable password if target device requires one. :param port: The destination port used to connect to the target device. :param device_type: Class selection based on device type. :param verbose: Enable additional messages to standard output. :param global_delay_factor: Multiplication factor affecting Netmiko delays (default: 1). :param use_keys: Connect to target device using SSH keys. :param key_file: Filename path of the SSH key file to use. :param pkey: SSH key object to use. :param passphrase: Passphrase to use for encrypted key; password will be used for key decryption if not specified. :param disabled_algorithms: Dictionary of SSH algorithms to disable. Refer to the Paramiko documentation for a description of the expected format. :param allow_agent: Enable use of SSH key-agent. :param ssh_strict: Automatically reject unknown SSH host keys (default: False, which means unknown SSH host keys will be accepted). :param system_host_keys: Load host keys from the users known_hosts file. :param alt_host_keys: If `True` host keys will be loaded from the file specified in alt_key_file. :param alt_key_file: SSH host key file to use (if alt_host_keys=True). :param ssh_config_file: File name of OpenSSH configuration file. :param timeout: Connection timeout. :param session_timeout: Set a timeout for parallel requests. :param auth_timeout: Set a timeout (in seconds) to wait for an authentication response. :param banner_timeout: Set a timeout to wait for the SSH banner (pass to Paramiko). :param keepalive: Send SSH keepalive packets at a specific interval, in seconds. Currently defaults to 0, for backwards compatibility (it will not attempt to keep the connection alive). :param default_enter: Character(s) to send to correspond to enter key (default: \n). :param response_return: Character(s) to use in normalized return data to represent enter key (default: \n) :param fast_cli: Provide a way to optimize for performance. Converts select_delay_factor to select smallest of global and specific. Sets default global_delay_factor to .1 (default: True) :param session_log: File path or BufferedIOBase subclass object to write the session log to. :param session_log_record_writes: The session log generally only records channel reads due to eliminate command duplication due to command echo. You can enable this if you want to record both channel reads and channel writes in the log (default: False). :param session_log_file_mode: "write" or "append" for session_log file mode (default: "write") :param allow_auto_change: Allow automatic configuration changes for terminal settings. (default: False) :param encoding: Encoding to be used when writing bytes to the output channel. (default: ascii) :param sock: An open socket or socket-like object (such as a `.Channel`) to use for communication to the target host (default: None). :param global_cmd_verify: Control whether command echo verification is enabled or disabled (default: None). Global attribute takes precedence over function `cmd_verify` argument. Value of `None` indicates to use function `cmd_verify` argument. :param auto_connect: Control whether Netmiko automatically establishes the connection as part of the object creation (default: True). :param delay_factor_compat: Set send_command and send_command_timing back to using Netmiko 3.x behavior for delay_factor/global_delay_factor/max_loops. This argument will be eliminated in Netmiko 5.x (default: False). """ self.remote_conn: Union[ None, telnetlib.Telnet, paramiko.Channel, serial.Serial ] = None # Does the platform support a configuration mode self._config_mode = True self._read_buffer = "" self.delay_factor_compat = delay_factor_compat self.TELNET_RETURN = "\r\n" if default_enter is None: if "telnet" not in device_type: self.RETURN = "\n" else: self.RETURN = self.TELNET_RETURN else: self.RETURN = default_enter # Line Separator in response lines self.RESPONSE_RETURN = "\n" if response_return is None else response_return if ip: self.host = ip.strip() elif host: self.host = host.strip() if not ip and not host and "serial" not in device_type: raise ValueError("Either ip or host must be set") if port is None: if "telnet" in device_type: port = 23 else: port = 22 self.port = int(port) self.username = username self.password = password self.secret = secret self.device_type = device_type self.ansi_escape_codes = False self.verbose = verbose self.auth_timeout = auth_timeout self.banner_timeout = banner_timeout self.blocking_timeout = blocking_timeout self.conn_timeout = conn_timeout self.session_timeout = session_timeout self.timeout = timeout self.read_timeout_override = read_timeout_override self.keepalive = keepalive self.allow_auto_change = allow_auto_change self.encoding = encoding self.sock = sock self.fast_cli = fast_cli self._legacy_mode = _legacy_mode self.global_delay_factor = global_delay_factor self.global_cmd_verify = global_cmd_verify if self.fast_cli and self.global_delay_factor == 1: self.global_delay_factor = 0.1 self.session_log = None self._session_log_close = False # prevent logging secret data no_log = {} if self.password: no_log["password"] = self.password if self.secret: no_log["secret"] = self.secret log.addFilter(SecretsFilter(no_log=no_log)) # Netmiko will close the session_log if we open the file if session_log is not None: if isinstance(session_log, str): # If session_log is a string, open a file corresponding to string name. self.session_log = SessionLog( file_name=session_log, file_mode=session_log_file_mode, no_log=no_log, record_writes=session_log_record_writes, ) self.session_log.open() elif isinstance(session_log, io.BufferedIOBase): # In-memory buffer or an already open file handle self.session_log = SessionLog( buffered_io=session_log, no_log=no_log, record_writes=session_log_record_writes, ) else: raise ValueError( "session_log must be a path to a file, a file handle, " "or a BufferedIOBase subclass." ) # Default values self.serial_settings = { "port": "COM1", "baudrate": 9600, "bytesize": serial.EIGHTBITS, "parity": serial.PARITY_NONE, "stopbits": serial.STOPBITS_ONE, } if serial_settings is None: serial_settings = {} self.serial_settings.update(serial_settings) if "serial" in device_type: self.host = "serial" comm_port = self.serial_settings.pop("port") # Get the proper comm port reference if a name was enterred comm_port = check_serial_port(comm_port) self.serial_settings.update({"port": comm_port}) # set in set_base_prompt method self.base_prompt = "" self._session_locker = Lock() # determine if telnet or SSH if "_telnet" in device_type: self.protocol = "telnet" self.password = password or "" elif "_serial" in device_type: self.protocol = "serial" self.password = password or "" else: self.protocol = "ssh" self.key_policy: paramiko.client.MissingHostKeyPolicy if not ssh_strict: self.key_policy = paramiko.AutoAddPolicy() else: self.key_policy = paramiko.RejectPolicy() # Options for SSH host_keys self.use_keys = use_keys self.key_file = ( path.abspath(path.expanduser(key_file)) if key_file else None ) if self.use_keys is True: self._key_check() self.pkey = pkey self.passphrase = passphrase self.allow_agent = allow_agent self.system_host_keys = system_host_keys self.alt_host_keys = alt_host_keys self.alt_key_file = alt_key_file self.disabled_algorithms = disabled_algorithms or {} # For SSH proxy support self.ssh_config_file = ssh_config_file # Establish the remote connection if auto_connect: self._open() def _open(self) -> None: """Decouple connection creation from __init__ for mocking.""" self._modify_connection_params() self.establish_connection() self._try_session_preparation() def __enter__(self) -> "BaseConnection": """Establish a session using a Context Manager.""" return self def __exit__( self, exc_type: Optional[Type[BaseException]], exc_value: Optional[BaseException], traceback: Optional[TracebackType], ) -> None: """Gracefully close connection on Context Manager exit.""" self.disconnect() def _modify_connection_params(self) -> None: """Modify connection parameters prior to SSH connection.""" pass def _timeout_exceeded(self, start: float, msg: str = "Timeout exceeded!") -> bool: """Raise NetmikoTimeoutException if waiting too much in the serving queue. :param start: Initial start time to see if session lock timeout has been exceeded :type start: float (from time.time() call i.e. epoch time) :param msg: Exception message if timeout was exceeded :type msg: str """ if not start: # Must provide a comparison time return False if time.time() - start > self.session_timeout: # session_timeout exceeded raise NetmikoTimeoutException(msg) return False def _lock_netmiko_session(self, start: Optional[float] = None) -> bool: """Try to acquire the Netmiko session lock. If not available, wait in the queue until the channel is available again. :param start: Initial start time to measure the session timeout :type start: float (from time.time() call i.e. epoch time) """ if not start: start = time.time() # Wait here until the SSH channel lock is acquired or until session_timeout exceeded while not self._session_locker.acquire(False) and not self._timeout_exceeded( start, "The netmiko channel is not available!" ): time.sleep(0.1) return True def _unlock_netmiko_session(self) -> None: """ Release the channel at the end of the task. """ if self._session_locker.locked(): self._session_locker.release() def _autodetect_fs(self, cmd: str = "", pattern: str = "") -> str: raise NotImplementedError def _enter_shell(self) -> str: raise NotImplementedError def _return_cli(self) -> str: raise NotImplementedError def _key_check(self) -> bool: """Verify key_file exists.""" msg = f""" use_keys has been set to True, but specified key_file does not exist: use_keys: {self.use_keys} key_file: {self.key_file} """ if self.key_file is None: raise ValueError(msg) my_key_file = Path(self.key_file) if not my_key_file.is_file(): raise ValueError(msg) return True @lock_channel @log_writes def write_channel(self, out_data: str) -> None: """Generic method that will write data out the channel. :param out_data: data to be written to the channel :type out_data: str """ self.channel.write_channel(out_data) def is_alive(self) -> bool: """Returns a boolean flag with the state of the connection.""" null = chr(0) if self.remote_conn is None: log.error("Connection is not initialised, is_alive returns False") return False if self.protocol == "telnet": try: # Try sending IAC + NOP (IAC is telnet way of sending command) # IAC = Interpret as Command; it comes before the NOP. log.debug("Sending IAC + NOP") # Need to send multiple times to test connection assert isinstance(self.remote_conn, telnetlib.Telnet) telnet_socket = self.remote_conn.get_socket() telnet_socket.sendall(telnetlib.IAC + telnetlib.NOP) telnet_socket.sendall(telnetlib.IAC + telnetlib.NOP) telnet_socket.sendall(telnetlib.IAC + telnetlib.NOP) return True except AttributeError: return False else: # SSH try: # Try sending ASCII null byte to maintain the connection alive log.debug("Sending the NULL byte") self.write_channel(null) assert isinstance(self.remote_conn, paramiko.Channel) assert self.remote_conn.transport is not None result = self.remote_conn.transport.is_active() assert isinstance(result, bool) return result except (socket.error, EOFError): log.error("Unable to send", exc_info=True) # If unable to send, we can tell for sure that the connection is unusable return False return False @lock_channel def read_channel(self) -> str: """Generic handler that will read all the data from given channel.""" new_data = self.channel.read_channel() new_data = self.normalize_linefeeds(new_data) if self.ansi_escape_codes: new_data = self.strip_ansi_escape_codes(new_data) log.debug(f"read_channel: {new_data}") if self.session_log: self.session_log.write(new_data) # If data had been previously saved to the buffer, the prepend it to output # do post read_channel so session_log/log doesn't record buffered data twice if self._read_buffer: output = self._read_buffer + new_data self._read_buffer = "" else: output = new_data return output def read_until_pattern( self, pattern: str = "", read_timeout: float = 10.0, re_flags: int = 0, max_loops: Optional[int] = None, ) -> str: """Read channel until pattern is detected. Will return string up to and including pattern. Returns ReadTimeout if pattern not detected in read_timeout seconds. :param pattern: Regular expression pattern used to identify that reading is done. :param read_timeout: maximum time to wait looking for pattern. Will raise ReadTimeout. A read_timeout value of 0 will cause the loop to never timeout (i.e. it will keep reading indefinitely until pattern is detected. :param re_flags: regex flags used in conjunction with pattern (defaults to no flags). :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. """ if max_loops is not None: msg = """\n Netmiko 4.x has deprecated the use of max_loops with read_until_pattern. You should convert all uses of max_loops over to read_timeout=x where x is the total number of seconds to wait before timing out.\n""" warnings.warn(msg, DeprecationWarning) if self.read_timeout_override: read_timeout = self.read_timeout_override output = "" loop_delay = 0.01 start_time = time.time() # if read_timeout == 0 or 0.0 keep reading indefinitely while (time.time() - start_time < read_timeout) or (not read_timeout): output += self.read_channel() if re.search(pattern, output, flags=re_flags): results = re.split(pattern, output, maxsplit=1, flags=re_flags) # The string matched by pattern must be retained in the output string. # re.split will do this if capturing parenthesis are used. if len(results) == 2: # no capturing parenthesis, convert and try again. pattern = f"({pattern})" results = re.split(pattern, output, maxsplit=1, flags=re_flags) if len(results) != 3: # well, we tried msg = f"""Unable to successfully split output based on pattern: pattern={pattern} output={repr(output)} results={results} """ raise ReadException(msg) # Process such that everything before and including pattern is return. # Everything else is retained in the _read_buffer output, match_str, buffer = results output = output + match_str if buffer: self._read_buffer += buffer log.debug(f"Pattern found: {pattern} {output}") return output time.sleep(loop_delay) msg = f"""\n\nPattern not detected: {repr(pattern)} in output. Things you might try to fix this: 1. Adjust the regex pattern to better identify the terminating string. Note, in many situations the pattern is automatically based on the network device's prompt. 2. Increase the read_timeout to a larger value. You can also look at the Netmiko session_log or debug log for more information.\n\n""" raise ReadTimeout(msg) def read_channel_timing( self, last_read: float = 2.0, read_timeout: float = 120.0, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, ) -> str: """Read data on the channel based on timing delays. General pattern is keep reading until no new data is read. Once no new data is read wait `last_read` amount of time (one last read). As long as no new data, then return data. `read_timeout` is an absolute timer for how long to keep reading (which presupposes we are still getting new data). Setting `read_timeout` to zero will cause read_channel_timing to never expire based on an absolute timeout. It will only complete based on timeout based on their being no new data. :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. """ if delay_factor is not None or max_loops is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) if self.read_timeout_override: read_timeout = self.read_timeout_override # Time to delay in each read loop loop_delay = 0.1 channel_data = "" start_time = time.time() # Set read_timeout to 0 to never timeout while (time.time() - start_time < read_timeout) or (not read_timeout): time.sleep(loop_delay) new_data = self.read_channel() # gather new output if new_data: channel_data += new_data # if we have some output, but nothing new, then do the last read elif channel_data != "": # Make sure really done (i.e. no new data) time.sleep(last_read) new_data = self.read_channel() if not new_data: break else: channel_data += new_data else: msg = f"""\n read_channel_timing's absolute timer expired. The network device was continually outputting data for longer than {read_timeout} seconds. If this is expected i.e. the command you are executing is continually emitting data for a long period of time, then you can set 'read_timeout=x' seconds. If you want Netmiko to keep reading indefinitely (i.e. to only stop when there is no new data), then you can set 'read_timeout=0'. You can look at the Netmiko session_log or debug log for more information. """ raise ReadTimeout(msg) return channel_data def read_until_prompt( self, read_timeout: float = 10.0, read_entire_line: bool = False, re_flags: int = 0, max_loops: Optional[int] = None, ) -> str: """Read channel up to and including self.base_prompt.""" pattern = re.escape(self.base_prompt) if read_entire_line: pattern = f"{pattern}.*" return self.read_until_pattern( pattern=pattern, re_flags=re_flags, max_loops=max_loops, read_timeout=read_timeout, ) def read_until_prompt_or_pattern( self, pattern: str = "", read_timeout: float = 10.0, read_entire_line: bool = False, re_flags: int = 0, max_loops: Optional[int] = None, ) -> str: """Read until either self.base_prompt or pattern is detected.""" prompt_pattern = re.escape(self.base_prompt) if read_entire_line: prompt_pattern = f"{prompt_pattern}.*" if pattern: combined_pattern = r"(?:{}|{})".format(prompt_pattern, pattern) else: combined_pattern = prompt_pattern return self.read_until_pattern( pattern=combined_pattern, re_flags=re_flags, max_loops=max_loops, read_timeout=read_timeout, ) def serial_login( self, pri_prompt_terminator: str = r"#\s*$", alt_prompt_terminator: str = r">\s*$", username_pattern: str = r"(?:[Uu]ser:|sername|ogin)", pwd_pattern: str = r"assword", delay_factor: float = 1.0, max_loops: int = 20, ) -> str: return self.telnet_login( pri_prompt_terminator, alt_prompt_terminator, username_pattern, pwd_pattern, delay_factor, max_loops, ) def telnet_login( self, pri_prompt_terminator: str = r"#\s*$", alt_prompt_terminator: str = r">\s*$", username_pattern: str = r"(?:user:|username|login|user name)", pwd_pattern: str = r"assword", delay_factor: float = 1.0, max_loops: int = 20, ) -> str: """Telnet login. Can be username/password or just password. :param pri_prompt_terminator: Primary trailing delimiter for identifying a device prompt :param alt_prompt_terminator: Alternate trailing delimiter for identifying a device prompt :param username_pattern: Pattern used to identify the username prompt :param delay_factor: See __init__: global_delay_factor :param max_loops: Controls the wait time in conjunction with the delay_factor """ delay_factor = self.select_delay_factor(delay_factor) # Revert telnet_login back to old speeds/delays if delay_factor < 1: if not self._legacy_mode and self.fast_cli: delay_factor = 1 time.sleep(1 * delay_factor) output = "" return_msg = "" i = 1 while i <= max_loops: try: output = self.read_channel() return_msg += output # Search for username pattern / send username if re.search(username_pattern, output, flags=re.I): # Sometimes username/password must be terminated with "\r" and not "\r\n" self.write_channel(self.username + "\r") time.sleep(1 * delay_factor) output = self.read_channel() return_msg += output # Search for password pattern / send password if re.search(pwd_pattern, output, flags=re.I): # Sometimes username/password must be terminated with "\r" and not "\r\n" assert isinstance(self.password, str) self.write_channel(self.password + "\r") time.sleep(0.5 * delay_factor) output = self.read_channel() return_msg += output if re.search( pri_prompt_terminator, output, flags=re.M ) or re.search(alt_prompt_terminator, output, flags=re.M): return return_msg # Check if proper data received if re.search(pri_prompt_terminator, output, flags=re.M) or re.search( alt_prompt_terminator, output, flags=re.M ): return return_msg self.write_channel(self.TELNET_RETURN) time.sleep(0.5 * delay_factor) i += 1 except EOFError: assert self.remote_conn is not None self.remote_conn.close() msg = f"Login failed: {self.host}" raise NetmikoAuthenticationException(msg) # Last try to see if we already logged in self.write_channel(self.TELNET_RETURN) time.sleep(0.5 * delay_factor) output = self.read_channel() return_msg += output if re.search(pri_prompt_terminator, output, flags=re.M) or re.search( alt_prompt_terminator, output, flags=re.M ): return return_msg msg = f"Login failed: {self.host}" assert self.remote_conn is not None self.remote_conn.close() raise NetmikoAuthenticationException(msg) def _try_session_preparation(self, force_data: bool = True) -> None: """ In case of an exception happening during `session_preparation()` Netmiko should gracefully clean-up after itself. This might be challenging for library users to do since they do not have a reference to the object. This is possibly related to threads used in Paramiko. """ try: # Netmiko needs there to be data for session_preparation to work. if force_data: self.write_channel(self.RETURN) time.sleep(0.1) self.session_preparation() except Exception: self.disconnect() raise def session_preparation(self) -> None: """ Prepare the session after the connection has been established This method handles some differences that occur between various devices early on in the session. In general, it should include: self._test_channel_read(pattern=r"some_pattern") self.set_base_prompt() self.set_terminal_width() self.disable_paging() """ self._test_channel_read() self.set_base_prompt() self.set_terminal_width() self.disable_paging() def _use_ssh_config(self, dict_arg: Dict[str, Any]) -> Dict[str, Any]: """Update SSH connection parameters based on contents of SSH config file. :param dict_arg: Dictionary of SSH connection parameters """ connect_dict = dict_arg.copy() # Use SSHConfig to generate source content. assert self.ssh_config_file is not None full_path = path.abspath(path.expanduser(self.ssh_config_file)) source: Union[paramiko.config.SSHConfigDict, Dict[str, Any]] if path.exists(full_path): ssh_config_instance = paramiko.SSHConfig() with io.open(full_path, "rt", encoding="utf-8") as f: ssh_config_instance.parse(f) source = ssh_config_instance.lookup(self.host) else: source = {} # Keys get normalized to lower-case proxy: Optional[paramiko.proxy.ProxyCommand] if "proxycommand" in source: proxy = paramiko.ProxyCommand(source["proxycommand"]) elif "proxyjump" in source: hops = list(reversed(source["proxyjump"].split(","))) if len(hops) > 1: raise ValueError( "ProxyJump with more than one proxy server is not supported." ) port = source.get("port", self.port) host = source.get("hostname", self.host) # -F {full_path} forces the continued use of the same SSH config file cmd = "ssh -F {} -W {}:{} {}".format(full_path, host, port, hops[0]) proxy = paramiko.ProxyCommand(cmd) else: proxy = None # Only update 'hostname', 'sock', 'port', and 'username' # For 'port' and 'username' only update if using object defaults if connect_dict["port"] == 22: connect_dict["port"] = int(source.get("port", self.port)) if connect_dict["username"] == "": connect_dict["username"] = source.get("user", self.username) if proxy: connect_dict["sock"] = proxy connect_dict["hostname"] = source.get("hostname", self.host) return connect_dict def _connect_params_dict(self) -> Dict[str, Any]: """Generate dictionary of Paramiko connection parameters.""" conn_dict = { "hostname": self.host, "port": self.port, "username": self.username, "password": self.password, "look_for_keys": self.use_keys, "allow_agent": self.allow_agent, "key_filename": self.key_file, "pkey": self.pkey, "passphrase": self.passphrase, "disabled_algorithms": self.disabled_algorithms, "timeout": self.conn_timeout, "auth_timeout": self.auth_timeout, "banner_timeout": self.banner_timeout, "sock": self.sock, } # Check if using SSH 'config' file mainly for SSH proxy support if self.ssh_config_file: conn_dict = self._use_ssh_config(conn_dict) return conn_dict def _sanitize_output( self, output: str, strip_command: bool = False, command_string: Optional[str] = None, strip_prompt: bool = False, ) -> str: """Strip out command echo and trailing router prompt.""" if strip_command and command_string: command_string = self.normalize_linefeeds(command_string) output = self.strip_command(command_string, output) if strip_prompt: output = self.strip_prompt(output) return output def establish_connection(self, width: int = 511, height: int = 1000) -> None: """Establish SSH connection to the network device Timeout will generate a NetmikoTimeoutException Authentication failure will generate a NetmikoAuthenticationException :param width: Specified width of the VT100 terminal window (default: 511) :type width: int :param height: Specified height of the VT100 terminal window (default: 1000) :type height: int """ self.channel: Channel if self.protocol == "telnet": self.remote_conn = telnetlib.Telnet( self.host, port=self.port, timeout=self.timeout ) # Migrating communication to channel class self.channel = TelnetChannel(conn=self.remote_conn, encoding=self.encoding) self.telnet_login() elif self.protocol == "serial": self.remote_conn = serial.Serial(**self.serial_settings) self.channel = SerialChannel(conn=self.remote_conn, encoding=self.encoding) self.serial_login() elif self.protocol == "ssh": ssh_connect_params = self._connect_params_dict() self.remote_conn_pre: Optional[paramiko.SSHClient] self.remote_conn_pre = self._build_ssh_client() # initiate SSH connection try: self.remote_conn_pre.connect(**ssh_connect_params) except socket.error as conn_error: self.paramiko_cleanup() msg = f"""TCP connection to device failed. Common causes of this problem are: 1. Incorrect hostname or IP address. 2. Wrong TCP port. 3. Intermediate firewall blocking access. Device settings: {self.device_type} {self.host}:{self.port} """ # Handle DNS failures separately if "Name or service not known" in str(conn_error): msg = ( f"DNS failure--the hostname you provided was not resolvable " f"in DNS: {self.host}:{self.port}" ) msg = msg.lstrip() raise NetmikoTimeoutException(msg) except paramiko.ssh_exception.AuthenticationException as auth_err: self.paramiko_cleanup() msg = f"""Authentication to device failed. Common causes of this problem are: 1. Invalid username and password 2. Incorrect SSH-key file 3. Connecting to the wrong device Device settings: {self.device_type} {self.host}:{self.port} """ msg += self.RETURN + str(auth_err) raise NetmikoAuthenticationException(msg) except paramiko.ssh_exception.SSHException as e: self.paramiko_cleanup() if "No existing session" in str(e): msg = ( "Paramiko: 'No existing session' error: " "try increasing 'conn_timeout' to 15 seconds or larger." ) raise NetmikoTimeoutException(msg) else: msg = f""" A paramiko SSHException occurred during connection creation: {str(e)} """ raise NetmikoTimeoutException(msg) if self.verbose: print(f"SSH connection established to {self.host}:{self.port}") # Use invoke_shell to establish an 'interactive session' self.remote_conn = self.remote_conn_pre.invoke_shell( term="vt100", width=width, height=height ) self.remote_conn.settimeout(self.blocking_timeout) if self.keepalive: assert isinstance(self.remote_conn.transport, paramiko.Transport) self.remote_conn.transport.set_keepalive(self.keepalive) # Migrating communication to channel class self.channel = SSHChannel(conn=self.remote_conn, encoding=self.encoding) self.special_login_handler() if self.verbose: print("Interactive SSH session established") return None def _test_channel_read(self, count: int = 40, pattern: str = "") -> str: """Try to read the channel (generally post login) verify you receive data back. :param count: the number of times to check the channel for data :param pattern: Regular expression pattern used to determine end of channel read """ def _increment_delay( main_delay: float, increment: float = 1.1, maximum: int = 8 ) -> float: """Increment sleep time to a maximum value.""" main_delay = main_delay * increment if main_delay >= maximum: main_delay = maximum return main_delay i = 0 delay_factor = self.select_delay_factor(delay_factor=0) if pattern: return self.read_until_pattern(pattern=pattern, read_timeout=20) main_delay = delay_factor * 0.1 time.sleep(main_delay * 10) new_data = "" while i <= count: new_data += self.read_channel_timing(read_timeout=20) if new_data: return new_data self.write_channel(self.RETURN) main_delay = _increment_delay(main_delay) time.sleep(main_delay) i += 1 raise NetmikoTimeoutException("Timed out waiting for data") def _build_ssh_client(self) -> paramiko.SSHClient: """Prepare for Paramiko SSH connection.""" # Create instance of SSHClient object remote_conn_pre = paramiko.SSHClient() # Load host_keys for better SSH security if self.system_host_keys: remote_conn_pre.load_system_host_keys() if self.alt_host_keys and path.isfile(self.alt_key_file): remote_conn_pre.load_host_keys(self.alt_key_file) # Default is to automatically add untrusted hosts (make sure appropriate for your env) remote_conn_pre.set_missing_host_key_policy(self.key_policy) return remote_conn_pre def select_delay_factor(self, delay_factor: float) -> float: """ Choose the greater of delay_factor or self.global_delay_factor (default). In fast_cli choose the lesser of delay_factor of self.global_delay_factor. :param delay_factor: See __init__: global_delay_factor :type delay_factor: int """ if self.fast_cli: if delay_factor and delay_factor <= self.global_delay_factor: return delay_factor else: return self.global_delay_factor else: if delay_factor >= self.global_delay_factor: return delay_factor else: return self.global_delay_factor def special_login_handler(self, delay_factor: float = 1.0) -> None: """Handler for devices like WLC, Extreme ERS that throw up characters prior to login.""" pass def disable_paging( self, command: str = "terminal length 0", delay_factor: Optional[float] = None, cmd_verify: bool = True, pattern: Optional[str] = None, ) -> str: """Disable paging default to a Cisco CLI method. :param command: Device command to disable pagination of output :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. """ if delay_factor is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) command = self.normalize_cmd(command) log.debug("In disable_paging") log.debug(f"Command: {command}") self.write_channel(command) # Make sure you read until you detect the command echo (avoid getting out of sync) if cmd_verify and self.global_cmd_verify is not False: output = self.read_until_pattern( pattern=re.escape(command.strip()), read_timeout=20 ) elif pattern: output = self.read_until_pattern(pattern=pattern, read_timeout=20) else: output = self.read_until_prompt() log.debug(f"{output}") log.debug("Exiting disable_paging") return output def set_terminal_width( self, command: str = "", delay_factor: Optional[float] = None, cmd_verify: bool = False, pattern: Optional[str] = None, ) -> str: """CLI terminals try to automatically adjust the line based on the width of the terminal. This causes the output to get distorted when accessed programmatically. Set terminal width to 511 which works on a broad set of devices. :param command: Command string to send to the device :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. """ if delay_factor is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) if not command: return "" command = self.normalize_cmd(command) self.write_channel(command) # Avoid cmd_verify here as terminal width must be set before doing cmd_verify if cmd_verify and self.global_cmd_verify is not False: output = self.read_until_pattern(pattern=re.escape(command.strip())) elif pattern: output = self.read_until_pattern(pattern=pattern) else: output = self.read_until_prompt() return output # Retry by sleeping .33 and then double sleep until 5 attempts (.33, .66, 1.32, etc) @retry( wait=wait_exponential(multiplier=0.33, min=0, max=5), stop=stop_after_attempt(5), reraise=True, ) def set_base_prompt( self, pri_prompt_terminator: str = "#", alt_prompt_terminator: str = ">", delay_factor: float = 1.0, pattern: Optional[str] = None, ) -> str: """Sets self.base_prompt Used as delimiter for stripping of trailing prompt in output. Should be set to something that is general and applies in multiple contexts. For Cisco devices this will be set to router hostname (i.e. prompt without > or #). This will be set on entering user exec or privileged exec on Cisco, but not when entering/exiting config mode. :param pri_prompt_terminator: Primary trailing delimiter for identifying a device prompt :param alt_prompt_terminator: Alternate trailing delimiter for identifying a device prompt :param delay_factor: See __init__: global_delay_factor :param pattern: Regular expression pattern to search for in find_prompt() call """ if pattern is None: if pri_prompt_terminator and alt_prompt_terminator: pri_term = re.escape(pri_prompt_terminator) alt_term = re.escape(alt_prompt_terminator) pattern = rf"({pri_term}|{alt_term})" elif pri_prompt_terminator: pattern = re.escape(pri_prompt_terminator) elif alt_prompt_terminator: pattern = re.escape(alt_prompt_terminator) if pattern: prompt = self.find_prompt(delay_factor=delay_factor, pattern=pattern) else: prompt = self.find_prompt(delay_factor=delay_factor) if not prompt[-1] in (pri_prompt_terminator, alt_prompt_terminator): raise ValueError(f"Router prompt not found: {repr(prompt)}") # If all we have is the 'terminator' just use that :-( if len(prompt) == 1: self.base_prompt = prompt else: # Strip off trailing terminator self.base_prompt = prompt[:-1] return self.base_prompt def find_prompt( self, delay_factor: float = 1.0, pattern: Optional[str] = None ) -> str: """Finds the current network device prompt, last line only. :param delay_factor: See __init__: global_delay_factor :type delay_factor: int :param pattern: Regular expression pattern to determine whether prompt is valid """ delay_factor = self.select_delay_factor(delay_factor) sleep_time = delay_factor * 0.25 self.clear_buffer() self.write_channel(self.RETURN) if pattern: prompt = self.read_until_pattern(pattern=pattern) else: # Initial read time.sleep(sleep_time) prompt = self.read_channel().strip() count = 0 while count <= 12 and not prompt: if not prompt: self.write_channel(self.RETURN) time.sleep(sleep_time) prompt = self.read_channel().strip() if sleep_time <= 3: # Double the sleep_time when it is small sleep_time *= 2 else: sleep_time += 1 count += 1 # If multiple lines in the output take the last line prompt = prompt.split(self.RESPONSE_RETURN)[-1] prompt = prompt.strip() self.clear_buffer() if not prompt: raise ValueError(f"Unable to find prompt: {prompt}") log.debug(f"[find_prompt()]: prompt is {prompt}") return prompt def clear_buffer( self, backoff: bool = True, backoff_max: float = 3.0, delay_factor: Optional[float] = None, ) -> str: """Read any data available in the channel.""" if delay_factor is None: delay_factor = self.global_delay_factor sleep_time = 0.1 * delay_factor output = "" for _ in range(10): time.sleep(sleep_time) data = self.read_channel() data = self.strip_ansi_escape_codes(data) output += data if not data: break # Double sleep time each time we detect data log.debug("Clear buffer detects data in the channel") if backoff: sleep_time *= 2 sleep_time = backoff_max if sleep_time >= backoff_max else sleep_time return output def command_echo_read(self, cmd: str, read_timeout: float) -> str: # Make sure you read until you detect the command echo (avoid getting out of sync) new_data = self.read_until_pattern( pattern=re.escape(cmd), read_timeout=read_timeout ) # There can be echoed prompts that haven't been cleared before the cmd echo # this can later mess up the trailing prompt pattern detection. Clear this out. lines = new_data.split(cmd) if len(lines) == 2: # lines[-1] should realistically just be the null string new_data = f"{cmd}{lines[-1]}" else: # cmd exists in the output multiple times? Just retain the original output pass return new_data @select_cmd_verify def send_command_timing( self, command_string: str, last_read: float = 2.0, read_timeout: float = 120.0, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, strip_prompt: bool = True, strip_command: bool = True, normalize: bool = True, use_textfsm: bool = False, textfsm_template: Optional[str] = None, use_ttp: bool = False, ttp_template: Optional[str] = None, use_genie: bool = False, cmd_verify: bool = False, ) -> Union[str, List[Any], Dict[str, Any]]: """Execute command_string on the SSH channel using a delay-based mechanism. Generally used for show commands. :param command_string: The command to be executed on the remote device. :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param strip_prompt: Remove the trailing router prompt from the output (default: True). :param strip_command: Remove the echo of the command from the output (default: True). :param normalize: Ensure the proper enter is sent at end of command (default: True). :param use_textfsm: Process command output through TextFSM template (default: False). :param textfsm_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None). :param use_ttp: Process command output through TTP template (default: False). :param ttp_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None). :param use_genie: Process command output through PyATS/Genie parser (default: False). :param cmd_verify: Verify command echo before proceeding (default: False). """ if delay_factor is not None or max_loops is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) output = "" new_data = "" if normalize: command_string = self.normalize_cmd(command_string) self.write_channel(command_string) cmd = command_string.strip() if cmd and cmd_verify: new_data = self.command_echo_read(cmd=cmd, read_timeout=10) output += new_data output += self.read_channel_timing( last_read=last_read, read_timeout=read_timeout ) output = self._sanitize_output( output, strip_command=strip_command, command_string=command_string, strip_prompt=strip_prompt, ) return_data = structured_data_converter( command=command_string, raw_data=output, platform=self.device_type, use_textfsm=use_textfsm, use_ttp=use_ttp, use_genie=use_genie, textfsm_template=textfsm_template, ttp_template=ttp_template, ) return return_data def _send_command_timing_str(self, *args: Any, **kwargs: Any) -> str: """Wrapper for `send_command_timing` method that always returns a string""" output = self.send_command_timing(*args, **kwargs) assert isinstance(output, str) return output def strip_prompt(self, a_string: str) -> str: """Strip the trailing router prompt from the output. :param a_string: Returned string from device :type a_string: str """ response_list = a_string.split(self.RESPONSE_RETURN) last_line = response_list[-1] if self.base_prompt in last_line: return self.RESPONSE_RETURN.join(response_list[:-1]) else: return a_string def _first_line_handler(self, data: str, search_pattern: str) -> Tuple[str, bool]: """ In certain situations the first line will get repainted which causes a false match on the terminating pattern. Filter this out. returns a tuple of (data, first_line_processed) Where data is the original data potentially with the first line modified and the first_line_processed is a flag indicating that we have handled the first line. """ try: # First line is the echo line containing the command. In certain situations # it gets repainted and needs filtered lines = data.split(self.RETURN) first_line = lines[0] if BACKSPACE_CHAR in first_line: pattern = search_pattern + r".*$" first_line = re.sub(pattern, repl="", string=first_line) lines[0] = first_line data = self.RETURN.join(lines) return (data, True) except IndexError: return (data, False) def _prompt_handler(self, auto_find_prompt: bool) -> str: if auto_find_prompt: try: prompt = self.find_prompt() except ValueError: prompt = self.base_prompt else: prompt = self.base_prompt return re.escape(prompt.strip()) @select_cmd_verify def send_command( self, command_string: str, expect_string: Optional[str] = None, read_timeout: float = 10.0, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, auto_find_prompt: bool = True, strip_prompt: bool = True, strip_command: bool = True, normalize: bool = True, use_textfsm: bool = False, textfsm_template: Optional[str] = None, use_ttp: bool = False, ttp_template: Optional[str] = None, use_genie: bool = False, cmd_verify: bool = True, ) -> Union[str, List[Any], Dict[str, Any]]: """Execute command_string on the SSH channel using a pattern-based mechanism. Generally used for show commands. By default this method will keep waiting to receive data until the network device prompt is detected. The current network device prompt will be determined automatically. :param command_string: The command to be executed on the remote device. :param expect_string: Regular expression pattern to use for determining end of output. If left blank will default to being based on router prompt. :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param strip_prompt: Remove the trailing router prompt from the output (default: True). :param strip_command: Remove the echo of the command from the output (default: True). :param normalize: Ensure the proper enter is sent at end of command (default: True). :param use_textfsm: Process command output through TextFSM template (default: False). :param textfsm_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None). :param use_ttp: Process command output through TTP template (default: False). :param ttp_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None). :param use_genie: Process command output through PyATS/Genie parser (default: False). :param cmd_verify: Verify command echo before proceeding (default: True). """ # Time to delay in each read loop loop_delay = 0.025 if self.read_timeout_override: read_timeout = self.read_timeout_override if self.delay_factor_compat: # For compatibility calculate the old equivalent read_timeout # i.e. what it would have been in Netmiko 3.x if delay_factor is None: tmp_delay_factor = self.global_delay_factor else: tmp_delay_factor = self.select_delay_factor(delay_factor) compat_timeout = calc_old_timeout( max_loops=max_loops, delay_factor=tmp_delay_factor, loop_delay=0.2, old_timeout=self.timeout, ) msg = f"""\n You have chosen to use Netmiko's delay_factor compatibility mode for send_command. This will revert Netmiko to behave similarly to how it did in Netmiko 3.x (i.e. to use delay_factor/global_delay_factor and max_loops). Using these parameters Netmiko has calculated an effective read_timeout of {compat_timeout} and will set the read_timeout to this value. Please convert your code to that new format i.e.: net_connect.send_command(cmd, read_timeout={compat_timeout}) And then disable delay_factor_compat. delay_factor_compat will be removed in Netmiko 5.x.\n""" warnings.warn(msg, DeprecationWarning) # Override the read_timeout with Netmiko 3.x way :-( read_timeout = compat_timeout else: # No need for two deprecation messages so only display this if not using # delay_factor_compat if delay_factor is not None or max_loops is not None: msg = """\n Netmiko 4.x has deprecated the use of delay_factor/max_loops with send_command. You should convert all uses of delay_factor and max_loops over to read_timeout=x where x is the total number of seconds to wait before timing out.\n""" warnings.warn(msg, DeprecationWarning) if expect_string is not None: search_pattern = expect_string else: search_pattern = self._prompt_handler(auto_find_prompt) if normalize: command_string = self.normalize_cmd(command_string) # Start the clock start_time = time.time() self.write_channel(command_string) new_data = "" cmd = command_string.strip() if cmd and cmd_verify: new_data = self.command_echo_read(cmd=cmd, read_timeout=10) MAX_CHARS = 2_000_000 DEQUE_SIZE = 20 output = "" # Check only the past N-reads. This is for the case where the output is # very large (i.e. searching a very large string for a pattern a whole bunch of times) past_n_reads: Deque[str] = deque(maxlen=DEQUE_SIZE) first_line_processed = False # Keep reading data until search_pattern is found or until read_timeout while time.time() - start_time < read_timeout: if new_data: output += new_data past_n_reads.append(new_data) # Case where we haven't processed the first_line yet (there is a potential issue # in the first line (in cases where the line is repainted). if not first_line_processed: output, first_line_processed = self._first_line_handler( output, search_pattern ) # Check if we have already found our pattern if re.search(search_pattern, output): break else: if len(output) <= MAX_CHARS: if re.search(search_pattern, output): break else: # Switch to deque mode if output is greater than MAX_CHARS # Check if pattern is in the past n reads if re.search(search_pattern, "".join(past_n_reads)): break time.sleep(loop_delay) new_data = self.read_channel() else: # nobreak msg = f""" Pattern not detected: {repr(search_pattern)} in output. Things you might try to fix this: 1. Explicitly set your pattern using the expect_string argument. 2. Increase the read_timeout to a larger value. You can also look at the Netmiko session_log or debug log for more information. """ raise ReadTimeout(msg) output = self._sanitize_output( output, strip_command=strip_command, command_string=command_string, strip_prompt=strip_prompt, ) return_val = structured_data_converter( command=command_string, raw_data=output, platform=self.device_type, use_textfsm=use_textfsm, use_ttp=use_ttp, use_genie=use_genie, textfsm_template=textfsm_template, ttp_template=ttp_template, ) return return_val def _send_command_str(self, *args: Any, **kwargs: Any) -> str: """Wrapper for `send_command` method that always returns a string""" output = self.send_command(*args, **kwargs) assert isinstance(output, str) return output def send_command_expect( self, *args: Any, **kwargs: Any ) -> Union[str, List[Any], Dict[str, Any]]: """Support previous name of send_command method.""" return self.send_command(*args, **kwargs) def _multiline_kwargs(self, **kwargs: Any) -> Dict[str, Any]: strip_prompt = kwargs.get("strip_prompt", False) kwargs["strip_prompt"] = strip_prompt strip_command = kwargs.get("strip_command", False) kwargs["strip_command"] = strip_command return kwargs def send_multiline( self, commands: Sequence[Union[str, List[str]]], multiline: bool = True, **kwargs: Any, ) -> str: """ commands should either be: commands = [[cmd1, expect1], [cmd2, expect2], ...]] Or commands = [cmd1, cmd2, cmd3, ...] Any expect_string that is a null-string will use pattern based on device's prompt (unless expect_string argument is passed in via kwargs. """ output = "" if multiline: kwargs = self._multiline_kwargs(**kwargs) default_expect_string = kwargs.pop("expect_string", None) if not default_expect_string: auto_find_prompt = kwargs.get("auto_find_prompt", True) default_expect_string = self._prompt_handler(auto_find_prompt) if commands and isinstance(commands[0], str): # If list of commands just send directly using default_expect_string (probably prompt) for cmd in commands: cmd = str(cmd) output += self._send_command_str( cmd, expect_string=default_expect_string, **kwargs ) else: # If list of lists, then first element is cmd and second element is expect_string for cmd_item in commands: assert not isinstance(cmd_item, str) cmd, expect_string = cmd_item if not expect_string: expect_string = default_expect_string output += self._send_command_str( cmd, expect_string=expect_string, **kwargs ) return output def send_multiline_timing( self, commands: Sequence[str], multiline: bool = True, **kwargs: Any ) -> str: if multiline: kwargs = self._multiline_kwargs(**kwargs) output = "" for cmd in commands: cmd = str(cmd) output += self._send_command_timing_str(cmd, **kwargs) return output @staticmethod def strip_backspaces(output: str) -> str: """Strip any backspace characters out of the output. :param output: Output obtained from a remote network device. :type output: str """ backspace_char = "\x08" return output.replace(backspace_char, "") def strip_command(self, command_string: str, output: str) -> str: """ Strip command_string from output string Cisco IOS adds backspaces into output for long commands (i.e. for commands that line wrap) :param command_string: The command string sent to the device :type command_string: str :param output: The returned output as a result of the command string sent to the device :type output: str """ backspace_char = "\x08" # Check for line wrap (remove backspaces) if backspace_char in output: output = output.replace(backspace_char, "") # Juniper has a weird case where the echoed command will be " \n" # i.e. there is an extra space there. cmd = command_string.strip() if output.startswith(cmd): output_lines = output.split(self.RESPONSE_RETURN) new_output = output_lines[1:] return self.RESPONSE_RETURN.join(new_output) else: # command_string isn't there; do nothing return output def normalize_linefeeds(self, a_string: str) -> str: """Convert `\r\r\n`,`\r\n`, `\n\r` to `\n.` :param a_string: A string that may have non-normalized line feeds i.e. output returned from device, or a device prompt :type a_string: str """ newline = re.compile("(\r\r\r\n|\r\r\n|\r\n|\n\r)") a_string = newline.sub(self.RESPONSE_RETURN, a_string) if self.RESPONSE_RETURN == "\n": # Convert any remaining \r to \n return re.sub("\r", self.RESPONSE_RETURN, a_string) else: return a_string def normalize_cmd(self, command: str) -> str: """Normalize CLI commands to have a single trailing newline. :param command: Command that may require line feed to be normalized :type command: str """ command = command.rstrip() command += self.RETURN return command def check_enable_mode(self, check_string: str = "") -> bool: """Check if in enable mode. Return boolean. :param check_string: Identification of privilege mode from device :type check_string: str """ self.write_channel(self.RETURN) output = self.read_until_prompt(read_entire_line=True) return check_string in output def enable( self, cmd: str = "", pattern: str = "ssword", enable_pattern: Optional[str] = None, re_flags: int = re.IGNORECASE, ) -> str: """Enter enable mode. :param cmd: Device command to enter enable mode :param pattern: pattern to search for indicating device is waiting for password :param enable_pattern: pattern indicating you have entered enable mode :param re_flags: Regular expression flags used in conjunction with pattern """ output = "" msg = ( "Failed to enter enable mode. Please ensure you pass " "the 'secret' argument to ConnectHandler." ) # Check if in enable mode if not self.check_enable_mode(): # Send "enable" mode command self.write_channel(self.normalize_cmd(cmd)) try: # Read the command echo end_data = "" if self.global_cmd_verify is not False: output += self.read_until_pattern(pattern=re.escape(cmd.strip())) end_data = output.split(cmd.strip())[-1] # Search for trailing prompt or password pattern if pattern not in output and self.base_prompt not in end_data: output += self.read_until_prompt_or_pattern( pattern=pattern, re_flags=re_flags ) # Send the "secret" in response to password pattern if re.search(pattern, output): self.write_channel(self.normalize_cmd(self.secret)) output += self.read_until_prompt() # Search for terminating pattern if defined if enable_pattern and not re.search(enable_pattern, output): output += self.read_until_pattern(pattern=enable_pattern) else: if not self.check_enable_mode(): raise ValueError(msg) except NetmikoTimeoutException: raise ValueError(msg) return output def exit_enable_mode(self, exit_command: str = "") -> str: """Exit enable mode. :param exit_command: Command that exits the session from privileged mode :type exit_command: str """ output = "" if self.check_enable_mode(): self.write_channel(self.normalize_cmd(exit_command)) output += self.read_until_prompt() if self.check_enable_mode(): raise ValueError("Failed to exit enable mode.") return output def check_config_mode( self, check_string: str = "", pattern: str = "", force_regex: bool = False ) -> bool: """Checks if the device is in configuration mode or not. :param check_string: Identification of configuration mode from the device :type check_string: str :param pattern: Pattern to terminate reading of channel :type pattern: str """ self.write_channel(self.RETURN) # You can encounter an issue here (on router name changes) prefer delay-based solution if not pattern: output = self.read_channel_timing(read_timeout=10.0) else: output = self.read_until_pattern(pattern=pattern) if force_regex: return bool(re.search(check_string, output)) else: return check_string in output def config_mode( self, config_command: str = "", pattern: str = "", re_flags: int = 0 ) -> str: """Enter into config_mode. :param config_command: Configuration command to send to the device :type config_command: str :param pattern: Pattern to terminate reading of channel :type pattern: str :param re_flags: Regular expression flags :type re_flags: RegexFlag """ output = "" if not self.check_config_mode(): self.write_channel(self.normalize_cmd(config_command)) # Make sure you read until you detect the command echo (avoid getting out of sync) if self.global_cmd_verify is not False: output += self.read_until_pattern( pattern=re.escape(config_command.strip()) ) if pattern: output += self.read_until_pattern(pattern=pattern, re_flags=re_flags) else: output += self.read_until_prompt(read_entire_line=True) if not self.check_config_mode(): raise ValueError("Failed to enter configuration mode.") return output def exit_config_mode(self, exit_config: str = "", pattern: str = "") -> str: """Exit from configuration mode. :param exit_config: Command to exit configuration mode :type exit_config: str :param pattern: Pattern to terminate reading of channel :type pattern: str """ output = "" if self.check_config_mode(): self.write_channel(self.normalize_cmd(exit_config)) # Make sure you read until you detect the command echo (avoid getting out of sync) if self.global_cmd_verify is not False: output += self.read_until_pattern( pattern=re.escape(exit_config.strip()) ) if pattern: output += self.read_until_pattern(pattern=pattern) else: output += self.read_until_prompt(read_entire_line=True) if self.check_config_mode(): raise ValueError("Failed to exit configuration mode") log.debug(f"exit_config_mode: {output}") return output def send_config_from_file( self, config_file: Union[str, bytes, "PathLike[Any]"], **kwargs: Any ) -> str: """ Send configuration commands down the SSH channel from a file. The file is processed line-by-line and each command is sent down the SSH channel. **kwargs are passed to send_config_set method. :param config_file: Path to configuration file to be sent to the device :param kwargs: params to be sent to send_config_set method """ with io.open(config_file, "rt", encoding="utf-8") as cfg_file: commands = cfg_file.readlines() return self.send_config_set(commands, **kwargs) def send_config_set( self, config_commands: Union[str, Sequence[str], Iterator[str], TextIO, None] = None, *, exit_config_mode: bool = True, read_timeout: Optional[float] = None, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, strip_prompt: bool = False, strip_command: bool = False, config_mode_command: Optional[str] = None, cmd_verify: bool = True, enter_config_mode: bool = True, error_pattern: str = "", terminator: str = r"#", bypass_commands: Optional[str] = None, ) -> str: """ Send configuration commands down the SSH channel. config_commands is an iterable containing all of the configuration commands. The commands will be executed one after the other. Automatically exits/enters configuration mode. :param config_commands: Multiple configuration commands to be sent to the device :param exit_config_mode: Determines whether or not to exit config mode after complete :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param strip_prompt: Determines whether or not to strip the prompt :param strip_command: Determines whether or not to strip the command :param read_timeout: Absolute timer to send to read_channel_timing. Should be rarely needed. :param config_mode_command: The command to enter into config mode :param cmd_verify: Whether or not to verify command echo for each command in config_set :param enter_config_mode: Do you enter config mode before sending config commands :param error_pattern: Regular expression pattern to detect config errors in the output. :param terminator: Regular expression pattern to use as an alternate terminator in certain situations. :param bypass_commands: Regular expression pattern indicating configuration commands where cmd_verify is automatically disabled. """ if self.global_cmd_verify is not None: cmd_verify = self.global_cmd_verify if delay_factor is not None or max_loops is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) # Calculate an equivalent read_timeout (if using old settings) # Eliminate in Netmiko 5.x if read_timeout is None: max_loops = 150 if max_loops is None else max_loops delay_factor = 1.0 if delay_factor is None else delay_factor # If delay_factor has been set, then look at global_delay_factor delay_factor = self.select_delay_factor(delay_factor) read_timeout = calc_old_timeout( max_loops=max_loops, delay_factor=delay_factor, loop_delay=0.1 ) if delay_factor is None: delay_factor = self.select_delay_factor(0) else: delay_factor = self.select_delay_factor(delay_factor) if read_timeout is None: read_timeout = 15 else: read_timeout = read_timeout if config_commands is None: return "" elif isinstance(config_commands, str): config_commands = (config_commands,) if not hasattr(config_commands, "__iter__"): raise ValueError("Invalid argument passed into send_config_set") if bypass_commands is None: # Commands where cmd_verify is automatically disabled reg-ex logical-or bypass_commands = r"^banner .*$" # Set bypass_commands="" to force no-bypass (usually for testing) bypass_detected = False if bypass_commands: # Make a copy of the iterator config_commands, config_commands_tmp = itertools.tee(config_commands, 2) bypass_detected = any( [True for cmd in config_commands_tmp if re.search(bypass_commands, cmd)] ) if bypass_detected: cmd_verify = False # Send config commands output = "" if enter_config_mode: if config_mode_command: output += self.config_mode(config_mode_command) else: output += self.config_mode() # Perform output gathering line-by-line (legacy way) if self.fast_cli and self._legacy_mode and not error_pattern: for cmd in config_commands: self.write_channel(self.normalize_cmd(cmd)) # Gather output output += self.read_channel_timing(read_timeout=read_timeout) elif not cmd_verify: for cmd in config_commands: self.write_channel(self.normalize_cmd(cmd)) time.sleep(delay_factor * 0.05) # Gather the output incrementally due to error_pattern requirements if error_pattern: output += self.read_channel_timing(read_timeout=read_timeout) if re.search(error_pattern, output, flags=re.M): msg = f"Invalid input detected at command: {cmd}" raise ConfigInvalidException(msg) # Standard output gathering (no error_pattern) if not error_pattern: output += self.read_channel_timing(read_timeout=read_timeout) else: for cmd in config_commands: self.write_channel(self.normalize_cmd(cmd)) # Make sure command is echoed output += self.read_until_pattern(pattern=re.escape(cmd.strip())) # Read until next prompt or terminator (#); the .*$ forces read of entire line pattern = f"(?:{re.escape(self.base_prompt)}.*$|{terminator}.*$)" output += self.read_until_pattern(pattern=pattern, re_flags=re.M) if error_pattern: if re.search(error_pattern, output, flags=re.M): msg = f"Invalid input detected at command: {cmd}" raise ConfigInvalidException(msg) if exit_config_mode: output += self.exit_config_mode() output = self._sanitize_output(output) log.debug(f"{output}") return output def strip_ansi_escape_codes(self, string_buffer: str) -> str: """ Remove any ANSI (VT100) ESC codes from the output http://en.wikipedia.org/wiki/ANSI_escape_code Note: this does not capture ALL possible ANSI Escape Codes only the ones I have encountered Current codes that are filtered: ESC = '\x1b' or chr(27) ESC = is the escape character [^ in hex ('\x1b') ESC[24;27H Position cursor ESC[?25h Show the cursor ESC[E Next line (HP does ESC-E) ESC[K Erase line from cursor to the end of line ESC[2K Erase entire line ESC[1;24r Enable scrolling from start to row end ESC[?6l Reset mode screen with options 640 x 200 monochrome (graphics) ESC[?7l Disable line wrapping ESC[2J Code erase display ESC[00;32m Color Green (30 to 37 are different colors) ESC[6n Get cursor position ESC[1D Move cursor position leftward by x characters (1 in this case) ESC[9999B Move cursor down N-lines (very large value is attempt to move to the very bottom of the screen). HP ProCurve and Cisco SG300 require this (possible others). :param string_buffer: The string to be processed to remove ANSI escape codes :type string_buffer: str """ # noqa code_position_cursor = chr(27) + r"\[\d+;\d+H" code_show_cursor = chr(27) + r"\[\?25h" code_next_line = chr(27) + r"E" code_erase_line_end = chr(27) + r"\[K" code_erase_line = chr(27) + r"\[2K" code_erase_start_line = chr(27) + r"\[K" code_enable_scroll = chr(27) + r"\[\d+;\d+r" code_insert_line = chr(27) + r"\[(\d+)L" code_carriage_return = chr(27) + r"\[1M" code_disable_line_wrapping = chr(27) + r"\[\?7l" code_reset_mode_screen_options = chr(27) + r"\[\?\d+l" code_reset_graphics_mode = chr(27) + r"\[00m" code_erase_display = chr(27) + r"\[2J" code_erase_display_0 = chr(27) + r"\[J" code_graphics_mode = chr(27) + r"\[\dm" code_graphics_mode1 = chr(27) + r"\[\d\d;\d\dm" code_graphics_mode2 = chr(27) + r"\[\d\d;\d\d;\d\dm" code_graphics_mode3 = chr(27) + r"\[(3|4)\dm" code_graphics_mode4 = chr(27) + r"\[(9|10)[0-7]m" code_get_cursor_position = chr(27) + r"\[6n" code_cursor_position = chr(27) + r"\[m" code_attrs_off = chr(27) + r"\[0m" code_reverse = chr(27) + r"\[7m" code_cursor_left = chr(27) + r"\[\d+D" code_cursor_forward = chr(27) + r"\[\d*C" code_cursor_up = chr(27) + r"\[\d*A" code_cursor_down = chr(27) + r"\[\d*B" code_wrap_around = chr(27) + r"\[\?7h" code_bracketed_paste_mode = chr(27) + r"\[\?2004h" code_set = [ code_position_cursor, code_show_cursor, code_erase_line, code_enable_scroll, code_erase_start_line, code_carriage_return, code_disable_line_wrapping, code_erase_line_end, code_reset_mode_screen_options, code_reset_graphics_mode, code_erase_display, code_graphics_mode, code_graphics_mode1, code_graphics_mode2, code_graphics_mode3, code_graphics_mode4, code_get_cursor_position, code_cursor_position, code_erase_display, code_erase_display_0, code_attrs_off, code_reverse, code_cursor_left, code_cursor_up, code_cursor_down, code_cursor_forward, code_wrap_around, code_bracketed_paste_mode, ] output = string_buffer for ansi_esc_code in code_set: output = re.sub(ansi_esc_code, "", output) # CODE_NEXT_LINE must substitute with return output = re.sub(code_next_line, self.RETURN, output) # Aruba and ProCurve switches can use code_insert_line for <enter> insert_line_match = re.search(code_insert_line, output) if insert_line_match: # Substitute each insert_line with a new <enter> count = int(insert_line_match.group(1)) output = re.sub(code_insert_line, count * self.RETURN, output) return output def cleanup(self, command: str = "") -> None: """Logout of the session on the network device plus any additional cleanup.""" pass def paramiko_cleanup(self) -> None: """Cleanup Paramiko to try to gracefully handle SSH session ending.""" if self.remote_conn_pre is not None: self.remote_conn_pre.close() del self.remote_conn_pre def disconnect(self) -> None: """Try to gracefully close the session.""" try: self.cleanup() except Exception: # Keep going on cleanup process even if exceptions pass try: if self.protocol == "ssh": self.paramiko_cleanup() elif self.protocol == "telnet": assert isinstance(self.remote_conn, telnetlib.Telnet) self.remote_conn.close() elif self.protocol == "serial": assert isinstance(self.remote_conn, serial.Serial) self.remote_conn.close() except Exception: # There have been race conditions observed on disconnect. pass finally: self.remote_conn_pre = None self.remote_conn = None if self.session_log: self.session_log.close() def commit(self) -> str: """Commit method for platforms that support this.""" raise AttributeError("Network device does not support 'commit()' method") def save_config( self, cmd: str = "", confirm: bool = False, confirm_response: str = "" ) -> str: """Not Implemented""" raise NotImplementedError def run_ttp( self, template: Union[str, bytes, "PathLike[Any]"], res_kwargs: Optional[Dict[str, Any]] = None, **kwargs: Any, ) -> Any: """ Run TTP template parsing by using input parameters to collect devices output. :param template: template content, OS path to template or reference to template within TTP templates collection in ttp://path/to/template.txt format :param res_kwargs: ``**res_kwargs`` arguments to pass to TTP result method :param kwargs: any other ``**kwargs`` to use for TTP object instantiation TTP template must have inputs defined together with below parameters. :param method: name of Netmiko connection object method to call, default ``send_command`` :param kwargs: Netmiko connection object method arguments :param commands: list of commands to collect Inputs' load could be of one of the supported formats and controlled by input's ``load`` attribute, supported values - python, yaml or json. For each input output collected from device and parsed accordingly. """ if res_kwargs is None: res_kwargs = {} return run_ttp_template( connection=self, template=template, res_kwargs=res_kwargs, **kwargs )Subclasses
- AudiocodeBase
- TelnetConnection
- CheckPointGaiaSSH
- CienaSaosBase
- CiscoWlcSSH
- CiscoBaseConnection
- NetscalerSSH
- DellIsilonSSH
- EricssonIposSSH
- F5TmshSSH
- FlexvnfSSH
- JuniperBase
- JuniperScreenOsSSH
- NetAppcDotSSH
- NokiaSrlSSH
- NokiaSros
- PaloAltoPanosBase
- PluribusSSH
- RadETXBase
- TerminalServer
- WatchguardFirewareSSH
- YamahaBase
Static methods
def strip_backspaces(output: str) ‑> str-
Strip any backspace characters out of the output.
:param output: Output obtained from a remote network device. :type output: str
Expand source code
@staticmethod def strip_backspaces(output: str) -> str: """Strip any backspace characters out of the output. :param output: Output obtained from a remote network device. :type output: str """ backspace_char = "\x08" return output.replace(backspace_char, "")
Methods
def check_config_mode(self, check_string: str = '', pattern: str = '', force_regex: bool = False) ‑> bool-
Checks if the device is in configuration mode or not.
:param check_string: Identification of configuration mode from the device :type check_string: str
:param pattern: Pattern to terminate reading of channel :type pattern: str
Expand source code
def check_config_mode( self, check_string: str = "", pattern: str = "", force_regex: bool = False ) -> bool: """Checks if the device is in configuration mode or not. :param check_string: Identification of configuration mode from the device :type check_string: str :param pattern: Pattern to terminate reading of channel :type pattern: str """ self.write_channel(self.RETURN) # You can encounter an issue here (on router name changes) prefer delay-based solution if not pattern: output = self.read_channel_timing(read_timeout=10.0) else: output = self.read_until_pattern(pattern=pattern) if force_regex: return bool(re.search(check_string, output)) else: return check_string in output def check_enable_mode(self, check_string: str = '') ‑> bool-
Check if in enable mode. Return boolean.
:param check_string: Identification of privilege mode from device :type check_string: str
Expand source code
def check_enable_mode(self, check_string: str = "") -> bool: """Check if in enable mode. Return boolean. :param check_string: Identification of privilege mode from device :type check_string: str """ self.write_channel(self.RETURN) output = self.read_until_prompt(read_entire_line=True) return check_string in output def cleanup(self, command: str = '') ‑> None-
Logout of the session on the network device plus any additional cleanup.
Expand source code
def cleanup(self, command: str = "") -> None: """Logout of the session on the network device plus any additional cleanup.""" pass def clear_buffer(self, backoff: bool = True, backoff_max: float = 3.0, delay_factor: Optional[float] = None) ‑> str-
Read any data available in the channel.
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def clear_buffer( self, backoff: bool = True, backoff_max: float = 3.0, delay_factor: Optional[float] = None, ) -> str: """Read any data available in the channel.""" if delay_factor is None: delay_factor = self.global_delay_factor sleep_time = 0.1 * delay_factor output = "" for _ in range(10): time.sleep(sleep_time) data = self.read_channel() data = self.strip_ansi_escape_codes(data) output += data if not data: break # Double sleep time each time we detect data log.debug("Clear buffer detects data in the channel") if backoff: sleep_time *= 2 sleep_time = backoff_max if sleep_time >= backoff_max else sleep_time return output def command_echo_read(self, cmd: str, read_timeout: float) ‑> str-
Expand source code
def command_echo_read(self, cmd: str, read_timeout: float) -> str: # Make sure you read until you detect the command echo (avoid getting out of sync) new_data = self.read_until_pattern( pattern=re.escape(cmd), read_timeout=read_timeout ) # There can be echoed prompts that haven't been cleared before the cmd echo # this can later mess up the trailing prompt pattern detection. Clear this out. lines = new_data.split(cmd) if len(lines) == 2: # lines[-1] should realistically just be the null string new_data = f"{cmd}{lines[-1]}" else: # cmd exists in the output multiple times? Just retain the original output pass return new_data def commit(self) ‑> str-
Commit method for platforms that support this.
Expand source code
def commit(self) -> str: """Commit method for platforms that support this.""" raise AttributeError("Network device does not support 'commit()' method") def config_mode(self, config_command: str = '', pattern: str = '', re_flags: int = 0) ‑> str-
Enter into config_mode.
:param config_command: Configuration command to send to the device :type config_command: str
:param pattern: Pattern to terminate reading of channel :type pattern: str
:param re_flags: Regular expression flags :type re_flags: RegexFlag
Expand source code
def config_mode( self, config_command: str = "", pattern: str = "", re_flags: int = 0 ) -> str: """Enter into config_mode. :param config_command: Configuration command to send to the device :type config_command: str :param pattern: Pattern to terminate reading of channel :type pattern: str :param re_flags: Regular expression flags :type re_flags: RegexFlag """ output = "" if not self.check_config_mode(): self.write_channel(self.normalize_cmd(config_command)) # Make sure you read until you detect the command echo (avoid getting out of sync) if self.global_cmd_verify is not False: output += self.read_until_pattern( pattern=re.escape(config_command.strip()) ) if pattern: output += self.read_until_pattern(pattern=pattern, re_flags=re_flags) else: output += self.read_until_prompt(read_entire_line=True) if not self.check_config_mode(): raise ValueError("Failed to enter configuration mode.") return output def disable_paging(self, command: str = 'terminal length 0', delay_factor: Optional[float] = None, cmd_verify: bool = True, pattern: Optional[str] = None) ‑> str-
Disable paging default to a Cisco CLI method.
:param command: Device command to disable pagination of output
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
Expand source code
def disable_paging( self, command: str = "terminal length 0", delay_factor: Optional[float] = None, cmd_verify: bool = True, pattern: Optional[str] = None, ) -> str: """Disable paging default to a Cisco CLI method. :param command: Device command to disable pagination of output :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. """ if delay_factor is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) command = self.normalize_cmd(command) log.debug("In disable_paging") log.debug(f"Command: {command}") self.write_channel(command) # Make sure you read until you detect the command echo (avoid getting out of sync) if cmd_verify and self.global_cmd_verify is not False: output = self.read_until_pattern( pattern=re.escape(command.strip()), read_timeout=20 ) elif pattern: output = self.read_until_pattern(pattern=pattern, read_timeout=20) else: output = self.read_until_prompt() log.debug(f"{output}") log.debug("Exiting disable_paging") return output def disconnect(self) ‑> None-
Try to gracefully close the session.
Expand source code
def disconnect(self) -> None: """Try to gracefully close the session.""" try: self.cleanup() except Exception: # Keep going on cleanup process even if exceptions pass try: if self.protocol == "ssh": self.paramiko_cleanup() elif self.protocol == "telnet": assert isinstance(self.remote_conn, telnetlib.Telnet) self.remote_conn.close() elif self.protocol == "serial": assert isinstance(self.remote_conn, serial.Serial) self.remote_conn.close() except Exception: # There have been race conditions observed on disconnect. pass finally: self.remote_conn_pre = None self.remote_conn = None if self.session_log: self.session_log.close() def enable(self, cmd: str = '', pattern: str = 'ssword', enable_pattern: Optional[str] = None, re_flags: int = re.IGNORECASE) ‑> str-
Enter enable mode.
:param cmd: Device command to enter enable mode
:param pattern: pattern to search for indicating device is waiting for password
:param enable_pattern: pattern indicating you have entered enable mode
:param re_flags: Regular expression flags used in conjunction with pattern
Expand source code
def enable( self, cmd: str = "", pattern: str = "ssword", enable_pattern: Optional[str] = None, re_flags: int = re.IGNORECASE, ) -> str: """Enter enable mode. :param cmd: Device command to enter enable mode :param pattern: pattern to search for indicating device is waiting for password :param enable_pattern: pattern indicating you have entered enable mode :param re_flags: Regular expression flags used in conjunction with pattern """ output = "" msg = ( "Failed to enter enable mode. Please ensure you pass " "the 'secret' argument to ConnectHandler." ) # Check if in enable mode if not self.check_enable_mode(): # Send "enable" mode command self.write_channel(self.normalize_cmd(cmd)) try: # Read the command echo end_data = "" if self.global_cmd_verify is not False: output += self.read_until_pattern(pattern=re.escape(cmd.strip())) end_data = output.split(cmd.strip())[-1] # Search for trailing prompt or password pattern if pattern not in output and self.base_prompt not in end_data: output += self.read_until_prompt_or_pattern( pattern=pattern, re_flags=re_flags ) # Send the "secret" in response to password pattern if re.search(pattern, output): self.write_channel(self.normalize_cmd(self.secret)) output += self.read_until_prompt() # Search for terminating pattern if defined if enable_pattern and not re.search(enable_pattern, output): output += self.read_until_pattern(pattern=enable_pattern) else: if not self.check_enable_mode(): raise ValueError(msg) except NetmikoTimeoutException: raise ValueError(msg) return output def establish_connection(self, width: int = 511, height: int = 1000) ‑> None-
Establish SSH connection to the network device
Timeout will generate a NetmikoTimeoutException Authentication failure will generate a NetmikoAuthenticationException
:param width: Specified width of the VT100 terminal window (default: 511) :type width: int
:param height: Specified height of the VT100 terminal window (default: 1000) :type height: int
Expand source code
def establish_connection(self, width: int = 511, height: int = 1000) -> None: """Establish SSH connection to the network device Timeout will generate a NetmikoTimeoutException Authentication failure will generate a NetmikoAuthenticationException :param width: Specified width of the VT100 terminal window (default: 511) :type width: int :param height: Specified height of the VT100 terminal window (default: 1000) :type height: int """ self.channel: Channel if self.protocol == "telnet": self.remote_conn = telnetlib.Telnet( self.host, port=self.port, timeout=self.timeout ) # Migrating communication to channel class self.channel = TelnetChannel(conn=self.remote_conn, encoding=self.encoding) self.telnet_login() elif self.protocol == "serial": self.remote_conn = serial.Serial(**self.serial_settings) self.channel = SerialChannel(conn=self.remote_conn, encoding=self.encoding) self.serial_login() elif self.protocol == "ssh": ssh_connect_params = self._connect_params_dict() self.remote_conn_pre: Optional[paramiko.SSHClient] self.remote_conn_pre = self._build_ssh_client() # initiate SSH connection try: self.remote_conn_pre.connect(**ssh_connect_params) except socket.error as conn_error: self.paramiko_cleanup() msg = f"""TCP connection to device failed. Common causes of this problem are: 1. Incorrect hostname or IP address. 2. Wrong TCP port. 3. Intermediate firewall blocking access. Device settings: {self.device_type} {self.host}:{self.port} """ # Handle DNS failures separately if "Name or service not known" in str(conn_error): msg = ( f"DNS failure--the hostname you provided was not resolvable " f"in DNS: {self.host}:{self.port}" ) msg = msg.lstrip() raise NetmikoTimeoutException(msg) except paramiko.ssh_exception.AuthenticationException as auth_err: self.paramiko_cleanup() msg = f"""Authentication to device failed. Common causes of this problem are: 1. Invalid username and password 2. Incorrect SSH-key file 3. Connecting to the wrong device Device settings: {self.device_type} {self.host}:{self.port} """ msg += self.RETURN + str(auth_err) raise NetmikoAuthenticationException(msg) except paramiko.ssh_exception.SSHException as e: self.paramiko_cleanup() if "No existing session" in str(e): msg = ( "Paramiko: 'No existing session' error: " "try increasing 'conn_timeout' to 15 seconds or larger." ) raise NetmikoTimeoutException(msg) else: msg = f""" A paramiko SSHException occurred during connection creation: {str(e)} """ raise NetmikoTimeoutException(msg) if self.verbose: print(f"SSH connection established to {self.host}:{self.port}") # Use invoke_shell to establish an 'interactive session' self.remote_conn = self.remote_conn_pre.invoke_shell( term="vt100", width=width, height=height ) self.remote_conn.settimeout(self.blocking_timeout) if self.keepalive: assert isinstance(self.remote_conn.transport, paramiko.Transport) self.remote_conn.transport.set_keepalive(self.keepalive) # Migrating communication to channel class self.channel = SSHChannel(conn=self.remote_conn, encoding=self.encoding) self.special_login_handler() if self.verbose: print("Interactive SSH session established") return None def exit_config_mode(self, exit_config: str = '', pattern: str = '') ‑> str-
Exit from configuration mode.
:param exit_config: Command to exit configuration mode :type exit_config: str
:param pattern: Pattern to terminate reading of channel :type pattern: str
Expand source code
def exit_config_mode(self, exit_config: str = "", pattern: str = "") -> str: """Exit from configuration mode. :param exit_config: Command to exit configuration mode :type exit_config: str :param pattern: Pattern to terminate reading of channel :type pattern: str """ output = "" if self.check_config_mode(): self.write_channel(self.normalize_cmd(exit_config)) # Make sure you read until you detect the command echo (avoid getting out of sync) if self.global_cmd_verify is not False: output += self.read_until_pattern( pattern=re.escape(exit_config.strip()) ) if pattern: output += self.read_until_pattern(pattern=pattern) else: output += self.read_until_prompt(read_entire_line=True) if self.check_config_mode(): raise ValueError("Failed to exit configuration mode") log.debug(f"exit_config_mode: {output}") return output def exit_enable_mode(self, exit_command: str = '') ‑> str-
Exit enable mode.
:param exit_command: Command that exits the session from privileged mode :type exit_command: str
Expand source code
def exit_enable_mode(self, exit_command: str = "") -> str: """Exit enable mode. :param exit_command: Command that exits the session from privileged mode :type exit_command: str """ output = "" if self.check_enable_mode(): self.write_channel(self.normalize_cmd(exit_command)) output += self.read_until_prompt() if self.check_enable_mode(): raise ValueError("Failed to exit enable mode.") return output def find_prompt(self, delay_factor: float = 1.0, pattern: Optional[str] = None) ‑> str-
Finds the current network device prompt, last line only.
:param delay_factor: See init: global_delay_factor :type delay_factor: int
:param pattern: Regular expression pattern to determine whether prompt is valid
Expand source code
def find_prompt( self, delay_factor: float = 1.0, pattern: Optional[str] = None ) -> str: """Finds the current network device prompt, last line only. :param delay_factor: See __init__: global_delay_factor :type delay_factor: int :param pattern: Regular expression pattern to determine whether prompt is valid """ delay_factor = self.select_delay_factor(delay_factor) sleep_time = delay_factor * 0.25 self.clear_buffer() self.write_channel(self.RETURN) if pattern: prompt = self.read_until_pattern(pattern=pattern) else: # Initial read time.sleep(sleep_time) prompt = self.read_channel().strip() count = 0 while count <= 12 and not prompt: if not prompt: self.write_channel(self.RETURN) time.sleep(sleep_time) prompt = self.read_channel().strip() if sleep_time <= 3: # Double the sleep_time when it is small sleep_time *= 2 else: sleep_time += 1 count += 1 # If multiple lines in the output take the last line prompt = prompt.split(self.RESPONSE_RETURN)[-1] prompt = prompt.strip() self.clear_buffer() if not prompt: raise ValueError(f"Unable to find prompt: {prompt}") log.debug(f"[find_prompt()]: prompt is {prompt}") return prompt def is_alive(self) ‑> bool-
Returns a boolean flag with the state of the connection.
Expand source code
def is_alive(self) -> bool: """Returns a boolean flag with the state of the connection.""" null = chr(0) if self.remote_conn is None: log.error("Connection is not initialised, is_alive returns False") return False if self.protocol == "telnet": try: # Try sending IAC + NOP (IAC is telnet way of sending command) # IAC = Interpret as Command; it comes before the NOP. log.debug("Sending IAC + NOP") # Need to send multiple times to test connection assert isinstance(self.remote_conn, telnetlib.Telnet) telnet_socket = self.remote_conn.get_socket() telnet_socket.sendall(telnetlib.IAC + telnetlib.NOP) telnet_socket.sendall(telnetlib.IAC + telnetlib.NOP) telnet_socket.sendall(telnetlib.IAC + telnetlib.NOP) return True except AttributeError: return False else: # SSH try: # Try sending ASCII null byte to maintain the connection alive log.debug("Sending the NULL byte") self.write_channel(null) assert isinstance(self.remote_conn, paramiko.Channel) assert self.remote_conn.transport is not None result = self.remote_conn.transport.is_active() assert isinstance(result, bool) return result except (socket.error, EOFError): log.error("Unable to send", exc_info=True) # If unable to send, we can tell for sure that the connection is unusable return False return False def normalize_cmd(self, command: str) ‑> str-
Normalize CLI commands to have a single trailing newline.
:param command: Command that may require line feed to be normalized :type command: str
Expand source code
def normalize_cmd(self, command: str) -> str: """Normalize CLI commands to have a single trailing newline. :param command: Command that may require line feed to be normalized :type command: str """ command = command.rstrip() command += self.RETURN return command def normalize_linefeeds(self, a_string: str) ‑> str-
Convert `
,,to.`:param a_string: A string that may have non-normalized line feeds i.e. output returned from device, or a device prompt :type a_string: strExpand source code
def normalize_linefeeds(self, a_string: str) -> str: """Convert `\r\r\n`,`\r\n`, `\n\r` to `\n.` :param a_string: A string that may have non-normalized line feeds i.e. output returned from device, or a device prompt :type a_string: str """ newline = re.compile("(\r\r\r\n|\r\r\n|\r\n|\n\r)") a_string = newline.sub(self.RESPONSE_RETURN, a_string) if self.RESPONSE_RETURN == "\n": # Convert any remaining \r to \n return re.sub("\r", self.RESPONSE_RETURN, a_string) else: return a_string def paramiko_cleanup(self) ‑> None-
Cleanup Paramiko to try to gracefully handle SSH session ending.
Expand source code
def paramiko_cleanup(self) -> None: """Cleanup Paramiko to try to gracefully handle SSH session ending.""" if self.remote_conn_pre is not None: self.remote_conn_pre.close() del self.remote_conn_pre def read_channel(self) ‑> str-
Generic handler that will read all the data from given channel.
Expand source code
@lock_channel def read_channel(self) -> str: """Generic handler that will read all the data from given channel.""" new_data = self.channel.read_channel() new_data = self.normalize_linefeeds(new_data) if self.ansi_escape_codes: new_data = self.strip_ansi_escape_codes(new_data) log.debug(f"read_channel: {new_data}") if self.session_log: self.session_log.write(new_data) # If data had been previously saved to the buffer, the prepend it to output # do post read_channel so session_log/log doesn't record buffered data twice if self._read_buffer: output = self._read_buffer + new_data self._read_buffer = "" else: output = new_data return output def read_channel_timing(self, last_read: float = 2.0, read_timeout: float = 120.0, delay_factor: Optional[float] = None, max_loops: Optional[int] = None) ‑> str-
Read data on the channel based on timing delays.
General pattern is keep reading until no new data is read. Once no new data is read wait
last_readamount of time (one last read). As long as no new data, then return data.read_timeoutis an absolute timer for how long to keep reading (which presupposes we are still getting new data).Setting
read_timeoutto zero will cause read_channel_timing to never expire based on an absolute timeout. It will only complete based on timeout based on their being no new data.:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
Expand source code
def read_channel_timing( self, last_read: float = 2.0, read_timeout: float = 120.0, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, ) -> str: """Read data on the channel based on timing delays. General pattern is keep reading until no new data is read. Once no new data is read wait `last_read` amount of time (one last read). As long as no new data, then return data. `read_timeout` is an absolute timer for how long to keep reading (which presupposes we are still getting new data). Setting `read_timeout` to zero will cause read_channel_timing to never expire based on an absolute timeout. It will only complete based on timeout based on their being no new data. :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. """ if delay_factor is not None or max_loops is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) if self.read_timeout_override: read_timeout = self.read_timeout_override # Time to delay in each read loop loop_delay = 0.1 channel_data = "" start_time = time.time() # Set read_timeout to 0 to never timeout while (time.time() - start_time < read_timeout) or (not read_timeout): time.sleep(loop_delay) new_data = self.read_channel() # gather new output if new_data: channel_data += new_data # if we have some output, but nothing new, then do the last read elif channel_data != "": # Make sure really done (i.e. no new data) time.sleep(last_read) new_data = self.read_channel() if not new_data: break else: channel_data += new_data else: msg = f"""\n read_channel_timing's absolute timer expired. The network device was continually outputting data for longer than {read_timeout} seconds. If this is expected i.e. the command you are executing is continually emitting data for a long period of time, then you can set 'read_timeout=x' seconds. If you want Netmiko to keep reading indefinitely (i.e. to only stop when there is no new data), then you can set 'read_timeout=0'. You can look at the Netmiko session_log or debug log for more information. """ raise ReadTimeout(msg) return channel_data def read_until_pattern(self, pattern: str = '', read_timeout: float = 10.0, re_flags: int = 0, max_loops: Optional[int] = None) ‑> str-
Read channel until pattern is detected.
Will return string up to and including pattern.
Returns ReadTimeout if pattern not detected in read_timeout seconds.
:param pattern: Regular expression pattern used to identify that reading is done.
:param read_timeout: maximum time to wait looking for pattern. Will raise ReadTimeout. A read_timeout value of 0 will cause the loop to never timeout (i.e. it will keep reading indefinitely until pattern is detected.
:param re_flags: regex flags used in conjunction with pattern (defaults to no flags).
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
Expand source code
def read_until_pattern( self, pattern: str = "", read_timeout: float = 10.0, re_flags: int = 0, max_loops: Optional[int] = None, ) -> str: """Read channel until pattern is detected. Will return string up to and including pattern. Returns ReadTimeout if pattern not detected in read_timeout seconds. :param pattern: Regular expression pattern used to identify that reading is done. :param read_timeout: maximum time to wait looking for pattern. Will raise ReadTimeout. A read_timeout value of 0 will cause the loop to never timeout (i.e. it will keep reading indefinitely until pattern is detected. :param re_flags: regex flags used in conjunction with pattern (defaults to no flags). :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. """ if max_loops is not None: msg = """\n Netmiko 4.x has deprecated the use of max_loops with read_until_pattern. You should convert all uses of max_loops over to read_timeout=x where x is the total number of seconds to wait before timing out.\n""" warnings.warn(msg, DeprecationWarning) if self.read_timeout_override: read_timeout = self.read_timeout_override output = "" loop_delay = 0.01 start_time = time.time() # if read_timeout == 0 or 0.0 keep reading indefinitely while (time.time() - start_time < read_timeout) or (not read_timeout): output += self.read_channel() if re.search(pattern, output, flags=re_flags): results = re.split(pattern, output, maxsplit=1, flags=re_flags) # The string matched by pattern must be retained in the output string. # re.split will do this if capturing parenthesis are used. if len(results) == 2: # no capturing parenthesis, convert and try again. pattern = f"({pattern})" results = re.split(pattern, output, maxsplit=1, flags=re_flags) if len(results) != 3: # well, we tried msg = f"""Unable to successfully split output based on pattern: pattern={pattern} output={repr(output)} results={results} """ raise ReadException(msg) # Process such that everything before and including pattern is return. # Everything else is retained in the _read_buffer output, match_str, buffer = results output = output + match_str if buffer: self._read_buffer += buffer log.debug(f"Pattern found: {pattern} {output}") return output time.sleep(loop_delay) msg = f"""\n\nPattern not detected: {repr(pattern)} in output. Things you might try to fix this: 1. Adjust the regex pattern to better identify the terminating string. Note, in many situations the pattern is automatically based on the network device's prompt. 2. Increase the read_timeout to a larger value. You can also look at the Netmiko session_log or debug log for more information.\n\n""" raise ReadTimeout(msg) def read_until_prompt(self, read_timeout: float = 10.0, read_entire_line: bool = False, re_flags: int = 0, max_loops: Optional[int] = None) ‑> str-
Read channel up to and including self.base_prompt.
Expand source code
def read_until_prompt( self, read_timeout: float = 10.0, read_entire_line: bool = False, re_flags: int = 0, max_loops: Optional[int] = None, ) -> str: """Read channel up to and including self.base_prompt.""" pattern = re.escape(self.base_prompt) if read_entire_line: pattern = f"{pattern}.*" return self.read_until_pattern( pattern=pattern, re_flags=re_flags, max_loops=max_loops, read_timeout=read_timeout, ) def read_until_prompt_or_pattern(self, pattern: str = '', read_timeout: float = 10.0, read_entire_line: bool = False, re_flags: int = 0, max_loops: Optional[int] = None) ‑> str-
Read until either self.base_prompt or pattern is detected.
Expand source code
def read_until_prompt_or_pattern( self, pattern: str = "", read_timeout: float = 10.0, read_entire_line: bool = False, re_flags: int = 0, max_loops: Optional[int] = None, ) -> str: """Read until either self.base_prompt or pattern is detected.""" prompt_pattern = re.escape(self.base_prompt) if read_entire_line: prompt_pattern = f"{prompt_pattern}.*" if pattern: combined_pattern = r"(?:{}|{})".format(prompt_pattern, pattern) else: combined_pattern = prompt_pattern return self.read_until_pattern( pattern=combined_pattern, re_flags=re_flags, max_loops=max_loops, read_timeout=read_timeout, ) def run_ttp(self, template: Union[str, bytes, ForwardRef('PathLike[Any]')], res_kwargs: Optional[Dict[str, Any]] = None, **kwargs: Any) ‑> Any-
Run TTP template parsing by using input parameters to collect devices output.
:param template: template content, OS path to template or reference to template within TTP templates collection in ttp://path/to/template.txt format
:param res_kwargs:
**res_kwargsarguments to pass to TTP result method:param kwargs: any other
**kwargsto use for TTP object instantiationTTP template must have inputs defined together with below parameters.
:param method: name of Netmiko connection object method to call, default
send_command:param kwargs: Netmiko connection object method arguments
:param commands: list of commands to collect
Inputs' load could be of one of the supported formats and controlled by input's
loadattribute, supported values - python, yaml or json. For each input output collected from device and parsed accordingly.Expand source code
def run_ttp( self, template: Union[str, bytes, "PathLike[Any]"], res_kwargs: Optional[Dict[str, Any]] = None, **kwargs: Any, ) -> Any: """ Run TTP template parsing by using input parameters to collect devices output. :param template: template content, OS path to template or reference to template within TTP templates collection in ttp://path/to/template.txt format :param res_kwargs: ``**res_kwargs`` arguments to pass to TTP result method :param kwargs: any other ``**kwargs`` to use for TTP object instantiation TTP template must have inputs defined together with below parameters. :param method: name of Netmiko connection object method to call, default ``send_command`` :param kwargs: Netmiko connection object method arguments :param commands: list of commands to collect Inputs' load could be of one of the supported formats and controlled by input's ``load`` attribute, supported values - python, yaml or json. For each input output collected from device and parsed accordingly. """ if res_kwargs is None: res_kwargs = {} return run_ttp_template( connection=self, template=template, res_kwargs=res_kwargs, **kwargs ) def save_config(self, cmd: str = '', confirm: bool = False, confirm_response: str = '') ‑> str-
Not Implemented
Expand source code
def save_config( self, cmd: str = "", confirm: bool = False, confirm_response: str = "" ) -> str: """Not Implemented""" raise NotImplementedError def select_delay_factor(self, delay_factor: float) ‑> float-
Choose the greater of delay_factor or self.global_delay_factor (default). In fast_cli choose the lesser of delay_factor of self.global_delay_factor.
:param delay_factor: See init: global_delay_factor :type delay_factor: int
Expand source code
def select_delay_factor(self, delay_factor: float) -> float: """ Choose the greater of delay_factor or self.global_delay_factor (default). In fast_cli choose the lesser of delay_factor of self.global_delay_factor. :param delay_factor: See __init__: global_delay_factor :type delay_factor: int """ if self.fast_cli: if delay_factor and delay_factor <= self.global_delay_factor: return delay_factor else: return self.global_delay_factor else: if delay_factor >= self.global_delay_factor: return delay_factor else: return self.global_delay_factor def send_command(self, command_string: str, expect_string: Optional[str] = None, read_timeout: float = 10.0, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, auto_find_prompt: bool = True, strip_prompt: bool = True, strip_command: bool = True, normalize: bool = True, use_textfsm: bool = False, textfsm_template: Optional[str] = None, use_ttp: bool = False, ttp_template: Optional[str] = None, use_genie: bool = False, cmd_verify: bool = True) ‑> Union[str, List[Any], Dict[str, Any]]-
Execute command_string on the SSH channel using a pattern-based mechanism. Generally used for show commands. By default this method will keep waiting to receive data until the network device prompt is detected. The current network device prompt will be determined automatically.
:param command_string: The command to be executed on the remote device.
:param expect_string: Regular expression pattern to use for determining end of output. If left blank will default to being based on router prompt.
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param strip_prompt: Remove the trailing router prompt from the output (default: True).
:param strip_command: Remove the echo of the command from the output (default: True).
:param normalize: Ensure the proper enter is sent at end of command (default: True).
:param use_textfsm: Process command output through TextFSM template (default: False).
:param textfsm_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None).
:param use_ttp: Process command output through TTP template (default: False).
:param ttp_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None).
:param use_genie: Process command output through PyATS/Genie parser (default: False).
:param cmd_verify: Verify command echo before proceeding (default: True).
Expand source code
@select_cmd_verify def send_command( self, command_string: str, expect_string: Optional[str] = None, read_timeout: float = 10.0, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, auto_find_prompt: bool = True, strip_prompt: bool = True, strip_command: bool = True, normalize: bool = True, use_textfsm: bool = False, textfsm_template: Optional[str] = None, use_ttp: bool = False, ttp_template: Optional[str] = None, use_genie: bool = False, cmd_verify: bool = True, ) -> Union[str, List[Any], Dict[str, Any]]: """Execute command_string on the SSH channel using a pattern-based mechanism. Generally used for show commands. By default this method will keep waiting to receive data until the network device prompt is detected. The current network device prompt will be determined automatically. :param command_string: The command to be executed on the remote device. :param expect_string: Regular expression pattern to use for determining end of output. If left blank will default to being based on router prompt. :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param strip_prompt: Remove the trailing router prompt from the output (default: True). :param strip_command: Remove the echo of the command from the output (default: True). :param normalize: Ensure the proper enter is sent at end of command (default: True). :param use_textfsm: Process command output through TextFSM template (default: False). :param textfsm_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None). :param use_ttp: Process command output through TTP template (default: False). :param ttp_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None). :param use_genie: Process command output through PyATS/Genie parser (default: False). :param cmd_verify: Verify command echo before proceeding (default: True). """ # Time to delay in each read loop loop_delay = 0.025 if self.read_timeout_override: read_timeout = self.read_timeout_override if self.delay_factor_compat: # For compatibility calculate the old equivalent read_timeout # i.e. what it would have been in Netmiko 3.x if delay_factor is None: tmp_delay_factor = self.global_delay_factor else: tmp_delay_factor = self.select_delay_factor(delay_factor) compat_timeout = calc_old_timeout( max_loops=max_loops, delay_factor=tmp_delay_factor, loop_delay=0.2, old_timeout=self.timeout, ) msg = f"""\n You have chosen to use Netmiko's delay_factor compatibility mode for send_command. This will revert Netmiko to behave similarly to how it did in Netmiko 3.x (i.e. to use delay_factor/global_delay_factor and max_loops). Using these parameters Netmiko has calculated an effective read_timeout of {compat_timeout} and will set the read_timeout to this value. Please convert your code to that new format i.e.: net_connect.send_command(cmd, read_timeout={compat_timeout}) And then disable delay_factor_compat. delay_factor_compat will be removed in Netmiko 5.x.\n""" warnings.warn(msg, DeprecationWarning) # Override the read_timeout with Netmiko 3.x way :-( read_timeout = compat_timeout else: # No need for two deprecation messages so only display this if not using # delay_factor_compat if delay_factor is not None or max_loops is not None: msg = """\n Netmiko 4.x has deprecated the use of delay_factor/max_loops with send_command. You should convert all uses of delay_factor and max_loops over to read_timeout=x where x is the total number of seconds to wait before timing out.\n""" warnings.warn(msg, DeprecationWarning) if expect_string is not None: search_pattern = expect_string else: search_pattern = self._prompt_handler(auto_find_prompt) if normalize: command_string = self.normalize_cmd(command_string) # Start the clock start_time = time.time() self.write_channel(command_string) new_data = "" cmd = command_string.strip() if cmd and cmd_verify: new_data = self.command_echo_read(cmd=cmd, read_timeout=10) MAX_CHARS = 2_000_000 DEQUE_SIZE = 20 output = "" # Check only the past N-reads. This is for the case where the output is # very large (i.e. searching a very large string for a pattern a whole bunch of times) past_n_reads: Deque[str] = deque(maxlen=DEQUE_SIZE) first_line_processed = False # Keep reading data until search_pattern is found or until read_timeout while time.time() - start_time < read_timeout: if new_data: output += new_data past_n_reads.append(new_data) # Case where we haven't processed the first_line yet (there is a potential issue # in the first line (in cases where the line is repainted). if not first_line_processed: output, first_line_processed = self._first_line_handler( output, search_pattern ) # Check if we have already found our pattern if re.search(search_pattern, output): break else: if len(output) <= MAX_CHARS: if re.search(search_pattern, output): break else: # Switch to deque mode if output is greater than MAX_CHARS # Check if pattern is in the past n reads if re.search(search_pattern, "".join(past_n_reads)): break time.sleep(loop_delay) new_data = self.read_channel() else: # nobreak msg = f""" Pattern not detected: {repr(search_pattern)} in output. Things you might try to fix this: 1. Explicitly set your pattern using the expect_string argument. 2. Increase the read_timeout to a larger value. You can also look at the Netmiko session_log or debug log for more information. """ raise ReadTimeout(msg) output = self._sanitize_output( output, strip_command=strip_command, command_string=command_string, strip_prompt=strip_prompt, ) return_val = structured_data_converter( command=command_string, raw_data=output, platform=self.device_type, use_textfsm=use_textfsm, use_ttp=use_ttp, use_genie=use_genie, textfsm_template=textfsm_template, ttp_template=ttp_template, ) return return_val def send_command_expect(self, *args: Any, **kwargs: Any) ‑> Union[str, List[Any], Dict[str, Any]]-
Support previous name of send_command method.
Expand source code
def send_command_expect( self, *args: Any, **kwargs: Any ) -> Union[str, List[Any], Dict[str, Any]]: """Support previous name of send_command method.""" return self.send_command(*args, **kwargs) def send_command_timing(self, command_string: str, last_read: float = 2.0, read_timeout: float = 120.0, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, strip_prompt: bool = True, strip_command: bool = True, normalize: bool = True, use_textfsm: bool = False, textfsm_template: Optional[str] = None, use_ttp: bool = False, ttp_template: Optional[str] = None, use_genie: bool = False, cmd_verify: bool = False) ‑> Union[str, List[Any], Dict[str, Any]]-
Execute command_string on the SSH channel using a delay-based mechanism. Generally used for show commands.
:param command_string: The command to be executed on the remote device.
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param strip_prompt: Remove the trailing router prompt from the output (default: True).
:param strip_command: Remove the echo of the command from the output (default: True).
:param normalize: Ensure the proper enter is sent at end of command (default: True).
:param use_textfsm: Process command output through TextFSM template (default: False).
:param textfsm_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None).
:param use_ttp: Process command output through TTP template (default: False).
:param ttp_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None).
:param use_genie: Process command output through PyATS/Genie parser (default: False).
:param cmd_verify: Verify command echo before proceeding (default: False).
Expand source code
@select_cmd_verify def send_command_timing( self, command_string: str, last_read: float = 2.0, read_timeout: float = 120.0, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, strip_prompt: bool = True, strip_command: bool = True, normalize: bool = True, use_textfsm: bool = False, textfsm_template: Optional[str] = None, use_ttp: bool = False, ttp_template: Optional[str] = None, use_genie: bool = False, cmd_verify: bool = False, ) -> Union[str, List[Any], Dict[str, Any]]: """Execute command_string on the SSH channel using a delay-based mechanism. Generally used for show commands. :param command_string: The command to be executed on the remote device. :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param strip_prompt: Remove the trailing router prompt from the output (default: True). :param strip_command: Remove the echo of the command from the output (default: True). :param normalize: Ensure the proper enter is sent at end of command (default: True). :param use_textfsm: Process command output through TextFSM template (default: False). :param textfsm_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None). :param use_ttp: Process command output through TTP template (default: False). :param ttp_template: Name of template to parse output with; can be fully qualified path, relative path, or name of file in current directory. (default: None). :param use_genie: Process command output through PyATS/Genie parser (default: False). :param cmd_verify: Verify command echo before proceeding (default: False). """ if delay_factor is not None or max_loops is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) output = "" new_data = "" if normalize: command_string = self.normalize_cmd(command_string) self.write_channel(command_string) cmd = command_string.strip() if cmd and cmd_verify: new_data = self.command_echo_read(cmd=cmd, read_timeout=10) output += new_data output += self.read_channel_timing( last_read=last_read, read_timeout=read_timeout ) output = self._sanitize_output( output, strip_command=strip_command, command_string=command_string, strip_prompt=strip_prompt, ) return_data = structured_data_converter( command=command_string, raw_data=output, platform=self.device_type, use_textfsm=use_textfsm, use_ttp=use_ttp, use_genie=use_genie, textfsm_template=textfsm_template, ttp_template=ttp_template, ) return return_data def send_config_from_file(self, config_file: Union[str, bytes, ForwardRef('PathLike[Any]')], **kwargs: Any) ‑> str-
Send configuration commands down the SSH channel from a file.
The file is processed line-by-line and each command is sent down the SSH channel.
**kwargs are passed to send_config_set method.
:param config_file: Path to configuration file to be sent to the device
:param kwargs: params to be sent to send_config_set method
Expand source code
def send_config_from_file( self, config_file: Union[str, bytes, "PathLike[Any]"], **kwargs: Any ) -> str: """ Send configuration commands down the SSH channel from a file. The file is processed line-by-line and each command is sent down the SSH channel. **kwargs are passed to send_config_set method. :param config_file: Path to configuration file to be sent to the device :param kwargs: params to be sent to send_config_set method """ with io.open(config_file, "rt", encoding="utf-8") as cfg_file: commands = cfg_file.readlines() return self.send_config_set(commands, **kwargs) def send_config_set(self, config_commands: Union[str, Sequence[str], Iterator[str], TextIO, ForwardRef(None)] = None, *, exit_config_mode: bool = True, read_timeout: Optional[float] = None, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, strip_prompt: bool = False, strip_command: bool = False, config_mode_command: Optional[str] = None, cmd_verify: bool = True, enter_config_mode: bool = True, error_pattern: str = '', terminator: str = '#', bypass_commands: Optional[str] = None) ‑> str-
Send configuration commands down the SSH channel.
config_commands is an iterable containing all of the configuration commands. The commands will be executed one after the other.
Automatically exits/enters configuration mode.
:param config_commands: Multiple configuration commands to be sent to the device
:param exit_config_mode: Determines whether or not to exit config mode after complete
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
:param strip_prompt: Determines whether or not to strip the prompt
:param strip_command: Determines whether or not to strip the command
:param read_timeout: Absolute timer to send to read_channel_timing. Should be rarely needed.
:param config_mode_command: The command to enter into config mode
:param cmd_verify: Whether or not to verify command echo for each command in config_set
:param enter_config_mode: Do you enter config mode before sending config commands
:param error_pattern: Regular expression pattern to detect config errors in the output.
:param terminator: Regular expression pattern to use as an alternate terminator in certain situations.
:param bypass_commands: Regular expression pattern indicating configuration commands where cmd_verify is automatically disabled.
Expand source code
def send_config_set( self, config_commands: Union[str, Sequence[str], Iterator[str], TextIO, None] = None, *, exit_config_mode: bool = True, read_timeout: Optional[float] = None, delay_factor: Optional[float] = None, max_loops: Optional[int] = None, strip_prompt: bool = False, strip_command: bool = False, config_mode_command: Optional[str] = None, cmd_verify: bool = True, enter_config_mode: bool = True, error_pattern: str = "", terminator: str = r"#", bypass_commands: Optional[str] = None, ) -> str: """ Send configuration commands down the SSH channel. config_commands is an iterable containing all of the configuration commands. The commands will be executed one after the other. Automatically exits/enters configuration mode. :param config_commands: Multiple configuration commands to be sent to the device :param exit_config_mode: Determines whether or not to exit config mode after complete :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param max_loops: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. :param strip_prompt: Determines whether or not to strip the prompt :param strip_command: Determines whether or not to strip the command :param read_timeout: Absolute timer to send to read_channel_timing. Should be rarely needed. :param config_mode_command: The command to enter into config mode :param cmd_verify: Whether or not to verify command echo for each command in config_set :param enter_config_mode: Do you enter config mode before sending config commands :param error_pattern: Regular expression pattern to detect config errors in the output. :param terminator: Regular expression pattern to use as an alternate terminator in certain situations. :param bypass_commands: Regular expression pattern indicating configuration commands where cmd_verify is automatically disabled. """ if self.global_cmd_verify is not None: cmd_verify = self.global_cmd_verify if delay_factor is not None or max_loops is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) # Calculate an equivalent read_timeout (if using old settings) # Eliminate in Netmiko 5.x if read_timeout is None: max_loops = 150 if max_loops is None else max_loops delay_factor = 1.0 if delay_factor is None else delay_factor # If delay_factor has been set, then look at global_delay_factor delay_factor = self.select_delay_factor(delay_factor) read_timeout = calc_old_timeout( max_loops=max_loops, delay_factor=delay_factor, loop_delay=0.1 ) if delay_factor is None: delay_factor = self.select_delay_factor(0) else: delay_factor = self.select_delay_factor(delay_factor) if read_timeout is None: read_timeout = 15 else: read_timeout = read_timeout if config_commands is None: return "" elif isinstance(config_commands, str): config_commands = (config_commands,) if not hasattr(config_commands, "__iter__"): raise ValueError("Invalid argument passed into send_config_set") if bypass_commands is None: # Commands where cmd_verify is automatically disabled reg-ex logical-or bypass_commands = r"^banner .*$" # Set bypass_commands="" to force no-bypass (usually for testing) bypass_detected = False if bypass_commands: # Make a copy of the iterator config_commands, config_commands_tmp = itertools.tee(config_commands, 2) bypass_detected = any( [True for cmd in config_commands_tmp if re.search(bypass_commands, cmd)] ) if bypass_detected: cmd_verify = False # Send config commands output = "" if enter_config_mode: if config_mode_command: output += self.config_mode(config_mode_command) else: output += self.config_mode() # Perform output gathering line-by-line (legacy way) if self.fast_cli and self._legacy_mode and not error_pattern: for cmd in config_commands: self.write_channel(self.normalize_cmd(cmd)) # Gather output output += self.read_channel_timing(read_timeout=read_timeout) elif not cmd_verify: for cmd in config_commands: self.write_channel(self.normalize_cmd(cmd)) time.sleep(delay_factor * 0.05) # Gather the output incrementally due to error_pattern requirements if error_pattern: output += self.read_channel_timing(read_timeout=read_timeout) if re.search(error_pattern, output, flags=re.M): msg = f"Invalid input detected at command: {cmd}" raise ConfigInvalidException(msg) # Standard output gathering (no error_pattern) if not error_pattern: output += self.read_channel_timing(read_timeout=read_timeout) else: for cmd in config_commands: self.write_channel(self.normalize_cmd(cmd)) # Make sure command is echoed output += self.read_until_pattern(pattern=re.escape(cmd.strip())) # Read until next prompt or terminator (#); the .*$ forces read of entire line pattern = f"(?:{re.escape(self.base_prompt)}.*$|{terminator}.*$)" output += self.read_until_pattern(pattern=pattern, re_flags=re.M) if error_pattern: if re.search(error_pattern, output, flags=re.M): msg = f"Invalid input detected at command: {cmd}" raise ConfigInvalidException(msg) if exit_config_mode: output += self.exit_config_mode() output = self._sanitize_output(output) log.debug(f"{output}") return output def send_multiline(self, commands: Sequence[Union[str, List[str]]], multiline: bool = True, **kwargs: Any) ‑> str-
commands should either be:
commands = [[cmd1, expect1], [cmd2, expect2], …]]
Or
commands = [cmd1, cmd2, cmd3, …]
Any expect_string that is a null-string will use pattern based on device's prompt (unless expect_string argument is passed in via kwargs.
Expand source code
def send_multiline( self, commands: Sequence[Union[str, List[str]]], multiline: bool = True, **kwargs: Any, ) -> str: """ commands should either be: commands = [[cmd1, expect1], [cmd2, expect2], ...]] Or commands = [cmd1, cmd2, cmd3, ...] Any expect_string that is a null-string will use pattern based on device's prompt (unless expect_string argument is passed in via kwargs. """ output = "" if multiline: kwargs = self._multiline_kwargs(**kwargs) default_expect_string = kwargs.pop("expect_string", None) if not default_expect_string: auto_find_prompt = kwargs.get("auto_find_prompt", True) default_expect_string = self._prompt_handler(auto_find_prompt) if commands and isinstance(commands[0], str): # If list of commands just send directly using default_expect_string (probably prompt) for cmd in commands: cmd = str(cmd) output += self._send_command_str( cmd, expect_string=default_expect_string, **kwargs ) else: # If list of lists, then first element is cmd and second element is expect_string for cmd_item in commands: assert not isinstance(cmd_item, str) cmd, expect_string = cmd_item if not expect_string: expect_string = default_expect_string output += self._send_command_str( cmd, expect_string=expect_string, **kwargs ) return output def send_multiline_timing(self, commands: Sequence[str], multiline: bool = True, **kwargs: Any) ‑> str-
Expand source code
def send_multiline_timing( self, commands: Sequence[str], multiline: bool = True, **kwargs: Any ) -> str: if multiline: kwargs = self._multiline_kwargs(**kwargs) output = "" for cmd in commands: cmd = str(cmd) output += self._send_command_timing_str(cmd, **kwargs) return output def serial_login(self, pri_prompt_terminator: str = '#\\s*$', alt_prompt_terminator: str = '>\\s*$', username_pattern: str = '(?:[Uu]ser:|sername|ogin)', pwd_pattern: str = 'assword', delay_factor: float = 1.0, max_loops: int = 20) ‑> str-
Expand source code
def serial_login( self, pri_prompt_terminator: str = r"#\s*$", alt_prompt_terminator: str = r">\s*$", username_pattern: str = r"(?:[Uu]ser:|sername|ogin)", pwd_pattern: str = r"assword", delay_factor: float = 1.0, max_loops: int = 20, ) -> str: return self.telnet_login( pri_prompt_terminator, alt_prompt_terminator, username_pattern, pwd_pattern, delay_factor, max_loops, ) def session_preparation(self) ‑> None-
Prepare the session after the connection has been established
This method handles some differences that occur between various devices early on in the session.
In general, it should include: self._test_channel_read(pattern=r"some_pattern") self.set_base_prompt() self.set_terminal_width() self.disable_paging()
Expand source code
def session_preparation(self) -> None: """ Prepare the session after the connection has been established This method handles some differences that occur between various devices early on in the session. In general, it should include: self._test_channel_read(pattern=r"some_pattern") self.set_base_prompt() self.set_terminal_width() self.disable_paging() """ self._test_channel_read() self.set_base_prompt() self.set_terminal_width() self.disable_paging() def set_base_prompt(self, pri_prompt_terminator: str = '#', alt_prompt_terminator: str = '>', delay_factor: float = 1.0, pattern: Optional[str] = None) ‑> str-
Sets self.base_prompt
Used as delimiter for stripping of trailing prompt in output.
Should be set to something that is general and applies in multiple contexts. For Cisco devices this will be set to router hostname (i.e. prompt without > or #).
This will be set on entering user exec or privileged exec on Cisco, but not when entering/exiting config mode.
:param pri_prompt_terminator: Primary trailing delimiter for identifying a device prompt
:param alt_prompt_terminator: Alternate trailing delimiter for identifying a device prompt
:param delay_factor: See init: global_delay_factor
:param pattern: Regular expression pattern to search for in find_prompt() call
Expand source code
@retry( wait=wait_exponential(multiplier=0.33, min=0, max=5), stop=stop_after_attempt(5), reraise=True, ) def set_base_prompt( self, pri_prompt_terminator: str = "#", alt_prompt_terminator: str = ">", delay_factor: float = 1.0, pattern: Optional[str] = None, ) -> str: """Sets self.base_prompt Used as delimiter for stripping of trailing prompt in output. Should be set to something that is general and applies in multiple contexts. For Cisco devices this will be set to router hostname (i.e. prompt without > or #). This will be set on entering user exec or privileged exec on Cisco, but not when entering/exiting config mode. :param pri_prompt_terminator: Primary trailing delimiter for identifying a device prompt :param alt_prompt_terminator: Alternate trailing delimiter for identifying a device prompt :param delay_factor: See __init__: global_delay_factor :param pattern: Regular expression pattern to search for in find_prompt() call """ if pattern is None: if pri_prompt_terminator and alt_prompt_terminator: pri_term = re.escape(pri_prompt_terminator) alt_term = re.escape(alt_prompt_terminator) pattern = rf"({pri_term}|{alt_term})" elif pri_prompt_terminator: pattern = re.escape(pri_prompt_terminator) elif alt_prompt_terminator: pattern = re.escape(alt_prompt_terminator) if pattern: prompt = self.find_prompt(delay_factor=delay_factor, pattern=pattern) else: prompt = self.find_prompt(delay_factor=delay_factor) if not prompt[-1] in (pri_prompt_terminator, alt_prompt_terminator): raise ValueError(f"Router prompt not found: {repr(prompt)}") # If all we have is the 'terminator' just use that :-( if len(prompt) == 1: self.base_prompt = prompt else: # Strip off trailing terminator self.base_prompt = prompt[:-1] return self.base_prompt def set_terminal_width(self, command: str = '', delay_factor: Optional[float] = None, cmd_verify: bool = False, pattern: Optional[str] = None) ‑> str-
CLI terminals try to automatically adjust the line based on the width of the terminal. This causes the output to get distorted when accessed programmatically.
Set terminal width to 511 which works on a broad set of devices.
:param command: Command string to send to the device
:param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5.
Expand source code
def set_terminal_width( self, command: str = "", delay_factor: Optional[float] = None, cmd_verify: bool = False, pattern: Optional[str] = None, ) -> str: """CLI terminals try to automatically adjust the line based on the width of the terminal. This causes the output to get distorted when accessed programmatically. Set terminal width to 511 which works on a broad set of devices. :param command: Command string to send to the device :param delay_factor: Deprecated in Netmiko 4.x. Will be eliminated in Netmiko 5. """ if delay_factor is not None: warnings.warn(DELAY_FACTOR_DEPR_SIMPLE_MSG, DeprecationWarning) if not command: return "" command = self.normalize_cmd(command) self.write_channel(command) # Avoid cmd_verify here as terminal width must be set before doing cmd_verify if cmd_verify and self.global_cmd_verify is not False: output = self.read_until_pattern(pattern=re.escape(command.strip())) elif pattern: output = self.read_until_pattern(pattern=pattern) else: output = self.read_until_prompt() return output def special_login_handler(self, delay_factor: float = 1.0) ‑> None-
Handler for devices like WLC, Extreme ERS that throw up characters prior to login.
Expand source code
def special_login_handler(self, delay_factor: float = 1.0) -> None: """Handler for devices like WLC, Extreme ERS that throw up characters prior to login.""" pass def strip_ansi_escape_codes(self, string_buffer: str) ‑> str-
Remove any ANSI (VT100) ESC codes from the output
http://en.wikipedia.org/wiki/ANSI_escape_code
Note: this does not capture ALL possible ANSI Escape Codes only the ones I have encountered
Current codes that are filtered: ESC = '' or chr(27) ESC = is the escape character [^ in hex ('') ESC[24;27H Position cursor ESC[?25h Show the cursor ESC[E Next line (HP does ESC-E) ESC[K Erase line from cursor to the end of line ESC[2K Erase entire line ESC[1;24r Enable scrolling from start to row end ESC[?6l Reset mode screen with options 640 x 200 monochrome (graphics) ESC[?7l Disable line wrapping ESC[2J Code erase display ESC[00;32m Color Green (30 to 37 are different colors) ESC[6n Get cursor position ESC[1D Move cursor position leftward by x characters (1 in this case) ESC[9999B Move cursor down N-lines (very large value is attempt to move to the very bottom of the screen).
HP ProCurve and Cisco SG300 require this (possible others).
:param string_buffer: The string to be processed to remove ANSI escape codes :type string_buffer: str
Expand source code
def strip_ansi_escape_codes(self, string_buffer: str) -> str: """ Remove any ANSI (VT100) ESC codes from the output http://en.wikipedia.org/wiki/ANSI_escape_code Note: this does not capture ALL possible ANSI Escape Codes only the ones I have encountered Current codes that are filtered: ESC = '\x1b' or chr(27) ESC = is the escape character [^ in hex ('\x1b') ESC[24;27H Position cursor ESC[?25h Show the cursor ESC[E Next line (HP does ESC-E) ESC[K Erase line from cursor to the end of line ESC[2K Erase entire line ESC[1;24r Enable scrolling from start to row end ESC[?6l Reset mode screen with options 640 x 200 monochrome (graphics) ESC[?7l Disable line wrapping ESC[2J Code erase display ESC[00;32m Color Green (30 to 37 are different colors) ESC[6n Get cursor position ESC[1D Move cursor position leftward by x characters (1 in this case) ESC[9999B Move cursor down N-lines (very large value is attempt to move to the very bottom of the screen). HP ProCurve and Cisco SG300 require this (possible others). :param string_buffer: The string to be processed to remove ANSI escape codes :type string_buffer: str """ # noqa code_position_cursor = chr(27) + r"\[\d+;\d+H" code_show_cursor = chr(27) + r"\[\?25h" code_next_line = chr(27) + r"E" code_erase_line_end = chr(27) + r"\[K" code_erase_line = chr(27) + r"\[2K" code_erase_start_line = chr(27) + r"\[K" code_enable_scroll = chr(27) + r"\[\d+;\d+r" code_insert_line = chr(27) + r"\[(\d+)L" code_carriage_return = chr(27) + r"\[1M" code_disable_line_wrapping = chr(27) + r"\[\?7l" code_reset_mode_screen_options = chr(27) + r"\[\?\d+l" code_reset_graphics_mode = chr(27) + r"\[00m" code_erase_display = chr(27) + r"\[2J" code_erase_display_0 = chr(27) + r"\[J" code_graphics_mode = chr(27) + r"\[\dm" code_graphics_mode1 = chr(27) + r"\[\d\d;\d\dm" code_graphics_mode2 = chr(27) + r"\[\d\d;\d\d;\d\dm" code_graphics_mode3 = chr(27) + r"\[(3|4)\dm" code_graphics_mode4 = chr(27) + r"\[(9|10)[0-7]m" code_get_cursor_position = chr(27) + r"\[6n" code_cursor_position = chr(27) + r"\[m" code_attrs_off = chr(27) + r"\[0m" code_reverse = chr(27) + r"\[7m" code_cursor_left = chr(27) + r"\[\d+D" code_cursor_forward = chr(27) + r"\[\d*C" code_cursor_up = chr(27) + r"\[\d*A" code_cursor_down = chr(27) + r"\[\d*B" code_wrap_around = chr(27) + r"\[\?7h" code_bracketed_paste_mode = chr(27) + r"\[\?2004h" code_set = [ code_position_cursor, code_show_cursor, code_erase_line, code_enable_scroll, code_erase_start_line, code_carriage_return, code_disable_line_wrapping, code_erase_line_end, code_reset_mode_screen_options, code_reset_graphics_mode, code_erase_display, code_graphics_mode, code_graphics_mode1, code_graphics_mode2, code_graphics_mode3, code_graphics_mode4, code_get_cursor_position, code_cursor_position, code_erase_display, code_erase_display_0, code_attrs_off, code_reverse, code_cursor_left, code_cursor_up, code_cursor_down, code_cursor_forward, code_wrap_around, code_bracketed_paste_mode, ] output = string_buffer for ansi_esc_code in code_set: output = re.sub(ansi_esc_code, "", output) # CODE_NEXT_LINE must substitute with return output = re.sub(code_next_line, self.RETURN, output) # Aruba and ProCurve switches can use code_insert_line for <enter> insert_line_match = re.search(code_insert_line, output) if insert_line_match: # Substitute each insert_line with a new <enter> count = int(insert_line_match.group(1)) output = re.sub(code_insert_line, count * self.RETURN, output) return output def strip_command(self, command_string: str, output: str) ‑> str-
Strip command_string from output string
Cisco IOS adds backspaces into output for long commands (i.e. for commands that line wrap)
:param command_string: The command string sent to the device :type command_string: str
:param output: The returned output as a result of the command string sent to the device :type output: str
Expand source code
def strip_command(self, command_string: str, output: str) -> str: """ Strip command_string from output string Cisco IOS adds backspaces into output for long commands (i.e. for commands that line wrap) :param command_string: The command string sent to the device :type command_string: str :param output: The returned output as a result of the command string sent to the device :type output: str """ backspace_char = "\x08" # Check for line wrap (remove backspaces) if backspace_char in output: output = output.replace(backspace_char, "") # Juniper has a weird case where the echoed command will be " \n" # i.e. there is an extra space there. cmd = command_string.strip() if output.startswith(cmd): output_lines = output.split(self.RESPONSE_RETURN) new_output = output_lines[1:] return self.RESPONSE_RETURN.join(new_output) else: # command_string isn't there; do nothing return output def strip_prompt(self, a_string: str) ‑> str-
Strip the trailing router prompt from the output.
:param a_string: Returned string from device :type a_string: str
Expand source code
def strip_prompt(self, a_string: str) -> str: """Strip the trailing router prompt from the output. :param a_string: Returned string from device :type a_string: str """ response_list = a_string.split(self.RESPONSE_RETURN) last_line = response_list[-1] if self.base_prompt in last_line: return self.RESPONSE_RETURN.join(response_list[:-1]) else: return a_string def telnet_login(self, pri_prompt_terminator: str = '#\\s*$', alt_prompt_terminator: str = '>\\s*$', username_pattern: str = '(?:user:|username|login|user name)', pwd_pattern: str = 'assword', delay_factor: float = 1.0, max_loops: int = 20) ‑> str-
Telnet login. Can be username/password or just password.
:param pri_prompt_terminator: Primary trailing delimiter for identifying a device prompt
:param alt_prompt_terminator: Alternate trailing delimiter for identifying a device prompt
:param username_pattern: Pattern used to identify the username prompt
:param delay_factor: See init: global_delay_factor
:param max_loops: Controls the wait time in conjunction with the delay_factor
Expand source code
def telnet_login( self, pri_prompt_terminator: str = r"#\s*$", alt_prompt_terminator: str = r">\s*$", username_pattern: str = r"(?:user:|username|login|user name)", pwd_pattern: str = r"assword", delay_factor: float = 1.0, max_loops: int = 20, ) -> str: """Telnet login. Can be username/password or just password. :param pri_prompt_terminator: Primary trailing delimiter for identifying a device prompt :param alt_prompt_terminator: Alternate trailing delimiter for identifying a device prompt :param username_pattern: Pattern used to identify the username prompt :param delay_factor: See __init__: global_delay_factor :param max_loops: Controls the wait time in conjunction with the delay_factor """ delay_factor = self.select_delay_factor(delay_factor) # Revert telnet_login back to old speeds/delays if delay_factor < 1: if not self._legacy_mode and self.fast_cli: delay_factor = 1 time.sleep(1 * delay_factor) output = "" return_msg = "" i = 1 while i <= max_loops: try: output = self.read_channel() return_msg += output # Search for username pattern / send username if re.search(username_pattern, output, flags=re.I): # Sometimes username/password must be terminated with "\r" and not "\r\n" self.write_channel(self.username + "\r") time.sleep(1 * delay_factor) output = self.read_channel() return_msg += output # Search for password pattern / send password if re.search(pwd_pattern, output, flags=re.I): # Sometimes username/password must be terminated with "\r" and not "\r\n" assert isinstance(self.password, str) self.write_channel(self.password + "\r") time.sleep(0.5 * delay_factor) output = self.read_channel() return_msg += output if re.search( pri_prompt_terminator, output, flags=re.M ) or re.search(alt_prompt_terminator, output, flags=re.M): return return_msg # Check if proper data received if re.search(pri_prompt_terminator, output, flags=re.M) or re.search( alt_prompt_terminator, output, flags=re.M ): return return_msg self.write_channel(self.TELNET_RETURN) time.sleep(0.5 * delay_factor) i += 1 except EOFError: assert self.remote_conn is not None self.remote_conn.close() msg = f"Login failed: {self.host}" raise NetmikoAuthenticationException(msg) # Last try to see if we already logged in self.write_channel(self.TELNET_RETURN) time.sleep(0.5 * delay_factor) output = self.read_channel() return_msg += output if re.search(pri_prompt_terminator, output, flags=re.M) or re.search( alt_prompt_terminator, output, flags=re.M ): return return_msg msg = f"Login failed: {self.host}" assert self.remote_conn is not None self.remote_conn.close() raise NetmikoAuthenticationException(msg) def write_channel(self, out_data: str) ‑> None-
Generic method that will write data out the channel.
:param out_data: data to be written to the channel :type out_data: str
Expand source code
@lock_channel @log_writes def write_channel(self, out_data: str) -> None: """Generic method that will write data out the channel. :param out_data: data to be written to the channel :type out_data: str """ self.channel.write_channel(out_data)
class SecretsFilter (no_log: Optional[Dict[Any, str]] = None)-
Filter instances are used to perform arbitrary filtering of LogRecords.
Loggers and Handlers can optionally use Filter instances to filter records as desired. The base filter class only allows events which are below a certain point in the logger hierarchy. For example, a filter initialized with "A.B" will allow events logged by loggers "A.B", "A.B.C", "A.B.C.D", "A.B.D" etc. but not "A.BB", "B.A.B" etc. If initialized with the empty string, all events are passed.
Initialize a filter.
Initialize with the name of the logger which, together with its children, will have its events allowed through the filter. If no name is specified, allow every event.
Expand source code
class SecretsFilter(logging.Filter): def __init__(self, no_log: Optional[Dict[Any, str]] = None) -> None: self.no_log = no_log def filter(self, record: logging.LogRecord) -> bool: """Removes secrets (no_log) from messages""" if self.no_log: for hidden_data in self.no_log.values(): record.msg = record.msg.replace(hidden_data, "********") return TrueAncestors
- logging.Filter
Methods
def filter(self, record: logging.LogRecord) ‑> bool-
Removes secrets (no_log) from messages
Expand source code
def filter(self, record: logging.LogRecord) -> bool: """Removes secrets (no_log) from messages""" if self.no_log: for hidden_data in self.no_log.values(): record.msg = record.msg.replace(hidden_data, "********") return True
class TelnetConnection (ip: str = '', host: str = '', username: str = '', password: Optional[str] = None, secret: str = '', port: Optional[int] = None, device_type: str = '', verbose: bool = False, global_delay_factor: float = 1.0, global_cmd_verify: Optional[bool] = None, use_keys: bool = False, key_file: Optional[str] = None, pkey: Optional[paramiko.pkey.PKey] = None, passphrase: Optional[str] = None, disabled_algorithms: Optional[Dict[str, Any]] = None, allow_agent: bool = False, ssh_strict: bool = False, system_host_keys: bool = False, alt_host_keys: bool = False, alt_key_file: str = '', ssh_config_file: Optional[str] = None, conn_timeout: int = 10, auth_timeout: Optional[int] = None, banner_timeout: int = 15, blocking_timeout: int = 20, timeout: int = 100, session_timeout: int = 60, read_timeout_override: Optional[float] = None, keepalive: int = 0, default_enter: Optional[str] = None, response_return: Optional[str] = None, serial_settings: Optional[Dict[str, Any]] = None, fast_cli: bool = True, session_log: Optional[SessionLog] = None, session_log_record_writes: bool = False, session_log_file_mode: str = 'write', allow_auto_change: bool = False, encoding: str = 'utf-8', sock: Optional[socket.socket] = None, auto_connect: bool = True, delay_factor_compat: bool = False)-
Defines vendor independent methods.
Otherwise method left as a stub method.
Initialize attributes for establishing connection to target device. :param ip: IP address of target device. Not required if <code>host</code> is provided. :param host: Hostname of target device. Not required if <code>ip</code> is provided. :param username: Username to authenticate against target device if required. :param password: Password to authenticate against target device if required. :param secret: The enable password if target device requires one. :param port: The destination port used to connect to the target device. :param device_type: Class selection based on device type. :param verbose: Enable additional messages to standard output. :param global_delay_factor: Multiplication factor affecting Netmiko delays (default: 1). :param use_keys: Connect to target device using SSH keys. :param key_file: Filename path of the SSH key file to use. :param pkey: SSH key object to use. :param passphrase: Passphrase to use for encrypted key; password will be used for key decryption if not specified. :param disabled_algorithms: Dictionary of SSH algorithms to disable. Refer to the Paramiko documentation for a description of the expected format. :param allow_agent: Enable use of SSH key-agent. :param ssh_strict: Automatically reject unknown SSH host keys (default: False, which means unknown SSH host keys will be accepted). :param system_host_keys: Load host keys from the users known_hosts file. :param alt_host_keys: If <code>True</code> host keys will be loaded from the file specified in alt_key_file. :param alt_key_file: SSH host key file to use (if alt_host_keys=True). :param ssh_config_file: File name of OpenSSH configuration file. :param timeout: Connection timeout. :param session_timeout: Set a timeout for parallel requests. :param auth_timeout: Set a timeout (in seconds) to wait for an authentication response. :param banner_timeout: Set a timeout to wait for the SSH banner (pass to Paramiko). :param keepalive: Send SSH keepalive packets at a specific interval, in seconds. Currently defaults to 0, for backwards compatibility (it will not attempt to keep the connection alive). :param default_enter: Character(s) to send to correspond to enter key (default:).
:param response_return: Character(s) to use in normalized return data to represent enter key (default:)
:param fast_cli: Provide a way to optimize for performance. Converts select_delay_factor to select smallest of global and specific. Sets default global_delay_factor to .1 (default: True) :param session_log: File path or BufferedIOBase subclass object to write the session log to. :param session_log_record_writes: The session log generally only records channel reads due to eliminate command duplication due to command echo. You can enable this if you want to record both channel reads and channel writes in the log (default: False). :param session_log_file_mode: "write" or "append" for session_log file mode (default: "write") :param allow_auto_change: Allow automatic configuration changes for terminal settings. (default: False) :param encoding: Encoding to be used when writing bytes to the output channel. (default: ascii) :param sock: An open socket or socket-like object (such as a <code>.Channel</code>) to use for communication to the target host (default: None). :param global_cmd_verify: Control whether command echo verification is enabled or disabled (default: None). Global attribute takes precedence over function <code>cmd\_verify</code> argument. Value of <code>None</code> indicates to use function <code>cmd\_verify</code> argument. :param auto_connect: Control whether Netmiko automatically establishes the connection as part of the object creation (default: True). :param delay_factor_compat: Set send_command and send_command_timing back to using Netmiko 3.x behavior for delay_factor/global_delay_factor/max_loops. This argument will be eliminated in Netmiko 5.x (default: False).Expand source code
class TelnetConnection(BaseConnection): passAncestors
Inherited members
BaseConnection:check_config_modecheck_enable_modecleanupclear_buffercommitconfig_modedisable_pagingdisconnectenableestablish_connectionexit_config_modeexit_enable_modefind_promptis_alivenormalize_cmdnormalize_linefeedsparamiko_cleanupread_channelread_channel_timingread_until_patternread_until_promptread_until_prompt_or_patternrun_ttpsave_configselect_delay_factorsend_commandsend_command_expectsend_command_timingsend_config_from_filesend_config_setsend_multilinesession_preparationset_base_promptset_terminal_widthspecial_login_handlerstrip_ansi_escape_codesstrip_backspacesstrip_commandstrip_prompttelnet_loginwrite_channel