Utilizing ncclient bind_addr parameter

[elinewman12]

Why does the current version of Junos not use the bind_addr optional parameter for providing a source address to bind when connecting Device objects? It would be an easy fix and at least my current team would heavily benefit from this addition. I had to create a fork from our currently used version of Junos (5 years old) but we couldn't upgrade to the latest version either way due to the lack of this feature.

[chidanandpujar]

Hi @elinewman12
Thanks,
we are analyzing the ncclient options - https://github.com/ncclient/ncclient/blob/master/ncclient/transport/ssh.py#L206

Thanks

[elinewman12]

@chidanandpujar I implemented the change on a fork but it uses version 2.3.0. So far, testing has proven successful with the use of bind_addr

[chidanandpujar]

HI @elinewman12
Thanks for the information .
Latest PyEZ release is 2.6.8 , I will check the feasibility and update you .

Thanks

[dineshbaburam91]

@elinewman12 Could you please provide more information on use case of the "bind_addr" argument in the ncclient code?
To validate and add testcases in junos-eznc

[rado120p]

I concur with the OP, it would be useful to be able to pass the "bind_addr" parameter when instantiating the Device object.
There are situations where the script is executed from a host which may have multiple IP addresses but only some of them may be reachable from the target device. The "bind_addr" parameter in ncclient's connect function allows specifying the desired source IP address that is used to initiate the TCP connection.

I've personally ended up creating fork of junos-eznc device.py (version 2.7.0) so that it accepts the bind_addr parameter and then passes it to the ncclient's "connect" function.

class Device(_Connection):

    def __init__(self, *vargs, **kvargs):
    <omitted>
        self._bind_addr = kvargs.get("bind_addr", None)


    def open(self, *vargs, **kvargs):
    <omitted>

            # open connection using ncclient transport
            self._conn = netconf_ssh.connect(
                host=self._hostname,
                port=self._port,
                sock_fd=self._sock_fd,
                username=self._auth_user,
                password=self._auth_password,
                hostkey_verify=False,
                key_filename=self._ssh_private_key_file,
                allow_agent=allow_agent,
                look_for_keys=look_for_keys,
                ssh_config=self._sshconf_lkup(),
                timeout=self._conn_open_timeout,
                bind_addr=self._bind_addr, <<----- 
                device_params={
                    "name": "junos",
                    "local": self.__class__.ON_JUNOS,
                    "use_filter": self._use_filter,
                },
            )

[dineshbaburam91]

Fixed #1340