autossh not working when executed in python

Question

I am trying to create ssh reverse tunnel. When I run the below command on terminal it works greate:

autossh -M 10876 -N -f -o PubkeyAuthentication=yes -o PasswordAuthentication=no -i /root/.ssh/id_rsa -R 6666:localhost:22 root@**.**.**.** -p 2233

But when I run it in python with os.system() or using subprocess it's not working. When I check the processes list the process is created and running and has no difference with the last method.(running directly in terminal)

python code:

command ='autossh -M 10876 -N -f -o PubkeyAuthentication=yes -o PasswordAuthentication=no -i /root/.ssh/id_rsa -R 6666:localhost:22 root@**.**.**.** -p 2233'
proc = subprocess.Popen(shlex.split(command), stdout=subprocess.PIPE, shell=True)

Any idea What's the problem?

Answer 1

when you are using shell=True, you don't want to use shlex.split() on the command arguments... it should just be a string.

Since you are passing args to Popen as a sequence, the first arg (autossh) is used as the command, and the rest of the args are actually passed to the shell, not to autossh.

So... you can either remove shell=True, or pass args as a string by removing use of shlex.split().

https://docs.python.org/2/library/subprocess.html#subprocess.Popen

Answer 2

It works for me in Windows10 (autossh in cygwin, Python 3.6) port = 6379; command = f'autossh -M 1{port} -N -f -C -L {port}:localhost:{port} root@acone2'; proc = subprocess.Popen(shlex.split(command), stdout=subprocess.PIPE, shell=True)