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pythonpython-3.xsshparamiko

SSH using Python Paramiko: How to detect SSH Server responding with string on successful connection

When I connect to my Ubuntu server via SSH using the terminal, it sometimes return a certain string then closes the connection.

$ ssh hello@my.server.com -i ~/.ssh/id_ed25519
container not found
Connection to 123.10.10.231 closed.
Connection to my.server.com closed.

Using paramiko in my Python script to connect to this server, how do I detect when this is happening?

Currently I'm doing the following to make the connection:

import paramiko

ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy)
    
ssh.connect("my.server.com", 22, userfoo, key_filename="/home/gameveloster/.ssh/id_ed25519")
stdin, stdout, stderr = ssh.exec_command('ls')
print(stdout.readlines(), stderr.readlines())

and getting the following output even when the server is not closing the SSH connection immediately on connecting.

DEBUG:paramiko.transport:[chan 0] EOF sent (0)
["Error: Your SSH client doesn't support PTY\n"] []
Solution

  • The server seems to need terminal to print that message.

    In general, it's not a good idea to enable terminal emulation, when automating commands. But if you need that message, you will probably have to do it. Use get_pty parameter of SSHClient.exec_command:

    stdin, stdout, stderr = ssh.exec_command('ls', get_pty=True)