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pythonparamiko

How do you execute multiple commands in a single session in Paramiko? (Python)

def exec_command(self, command, bufsize=-1):
    #print "Executing Command: "+command
    chan = self._transport.open_session()
    chan.exec_command(command)
    stdin = chan.makefile('wb', bufsize)
    stdout = chan.makefile('rb', bufsize)
    stderr = chan.makefile_stderr('rb', bufsize)
    return stdin, stdout, stderr

When executing a command in paramiko, it always resets the session when you run exec_command. I want to able to execute sudo or su and still have those privileges when I run another exec_command. Another example would be trying to exec_command("cd /") and then run exec_command again and have it be in the root directory. I know you can do something like exec_command("cd /; ls -l"), but I need to do it in separate function calls.

Solution

  • Non-Interactive use cases

    This is a non-interactive example... it sends cd tmp, ls and then exit.

    import sys
sys.stderr = open('/dev/null')       # Silence silly warnings from paramiko
import paramiko as pm
sys.stderr = sys.__stderr__
import os

class AllowAllKeys(pm.MissingHostKeyPolicy):
    def missing_host_key(self, client, hostname, key):
        return

HOST = '127.0.0.1'
USER = ''
PASSWORD = ''

client = pm.SSHClient()
client.load_system_host_keys()
client.load_host_keys(os.path.expanduser('~/.ssh/known_hosts'))
client.set_missing_host_key_policy(AllowAllKeys())
client.connect(HOST, username=USER, password=PASSWORD)

channel = client.invoke_shell()
stdin = channel.makefile('wb')
stdout = channel.makefile('rb')

stdin.write('''
cd tmp
ls
exit
''')
print stdout.read()

stdout.close()
stdin.close()
client.close()

    Interactive use cases

    If you have an interactive ssh use case, paramiko can handle it... I personally would drive interactive ssh sessions with scrapli.

    Listing all the ways I can think of to use paramiko interactively:

    I might have missed some libraries that use paramiko, but it should be clear that paramiko is used quite extensively by python libraries that control ssh sessions.