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Hello I am new to python. trying to use a list to ssh to my remote server

#!/usr/bin/python
import subprocess

node = ['node41', 'node42', 'node52']
link = ['eth0', 'eth0', 'eht0']

for i in range(len(node)):
       print node[i], s16d1[i]
       subprocess.call(["ssh", node[i], 'ip link show s16d1[i]'])

getting his error

Error:
Device "link[i]" does not exist.

How can I pass device link from the list ssh remote command?

thanks,

Quote:How can I pass device link from the list ssh remote command?

In shell you do it via:

ssh host "command"

Command is one argument.

In Python you've to use a list. Each element is a argument, the first argument is the binary itself.

command = ['ssh', 'node', 'ip link show eth0']
stdout = subprocess.check_output(command)

I think you're using Public-Key authentication. If you want to use password authentication, you have to do it different. There is a module for it: http://www.paramiko.org/

Finally this should work with Python 2.7 and Python 3.x:

#!/usr/bin/python
from __future__ import print_function
# to be compatible with Python 3.x, print is since Python 3 a function and no longer a statement
from subprocess import check_output
# using check_output instead of using Popen
# call returns the exit code


def get_links(nodes, links):
   for node, link in zip(nodes, links):
        # zip can zip lists together
        # and assigned to node, link 
        # now format the command for the target host
        ip_command = 'ip link show {}'.format(link)
        # finally make a list for the ssh command
        command = ['ssh', node, ip_command]
        # save output to stdout
        stdout = check_output(command)
        # just print it. You can process also the output
        print(stdout.decode())
        # or
        # return stdout
 

def main():
    # use plural for lists and not singular
    nodes = ['node41', 'node42', 'node52']
    links = ['eth0', 'eth0', 'eht0']
    get_links(nodes, links)


if __name__ == '__main__':
    main()

Thanks DeaD_EyE!
You hint of "ip_command = 'ip link show {}'.format(link)" helped

#!/usr/bin/python
import subprocess

node = ['node41', 'node42', 'node52']
link = ['eth0', 'eth0', 'eht0']

for i in range(len(node)):
     ip_command = 'ip link show {}'.format(link[i])
       print ip_command
       subprocess.call(["ssh", node[i], ip_command])

pythonnew

DeaD_EyE

pythonnew