Running Sudo Command with paramiko

First of all, have you tried in console with ssh [email protected] "sudo -S -p '' dmesg". If it also fails, then you might check the sshd settings and the sudoer settings.

If it works well, please add some echo between lines, so that we can know exactly when the exception was thrown. I highly doubt that you should change sudo dmesg to sudo -S -p '' dmesg.

You might also try my wrapper of paramiko. I can use it smoothly to access any CentOS/SuSE node and perform any commands (w/wo sudo privilege):

#!/usr/bin/python

from StringIO import StringIO
import paramiko 

class SshClient:
    "A wrapper of paramiko.SSHClient"
    TIMEOUT = 4

    def __init__(self, host, port, username, password, key=None, passphrase=None):
        self.username = username
        self.password = password
        self.client = paramiko.SSHClient()
        self.client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
        if key is not None:
            key = paramiko.RSAKey.from_private_key(StringIO(key), password=passphrase)
        self.client.connect(host, port, username=username, password=password, pkey=key, timeout=self.TIMEOUT)

    def close(self):
        if self.client is not None:
            self.client.close()
            self.client = None

    def execute(self, command, sudo=False):
        feed_password = False
        if sudo and self.username != "root":
            command = "sudo -S -p '' %s" % command
            feed_password = self.password is not None and len(self.password) > 0
        stdin, stdout, stderr = self.client.exec_command(command)
        if feed_password:
            stdin.write(self.password + "\n")
            stdin.flush()
        return {'out': stdout.readlines(), 
                'err': stderr.readlines(),
                'retval': stdout.channel.recv_exit_status()}

if __name__ == "__main__":
    client = SshClient(host="host", port=22, username="username", password='password') 
    try:
       ret = client.execute('dmesg', sudo=True)
       print "  ".join(ret["out"]), "  E ".join(ret["err"]), ret["retval"]
    finally:
      client.close()