title: ParallelSSHClient() not running command
body: <p>I am trying to use the Parallel-SSH Client in Python to run commands on multiple servers. However, while testing this package out, I am running into a problem that I can't seem to solve.</p>
  
  <p>Here is my code:</p>
  
  <pre><code>from pssh import ParallelSSHClient
  host = '172.24.1.1'
  user = 'XXXX'
  password = 'XXXX'
  client = ParallelSSHClient(host, user, password)
  output = client.run_command('ls -l')
  </code></pre>
  
  <p>Everytime I try to run this code it seems to give me the errors:</p>
  
  <pre><code>pssh.exceptions.ConnectionErrorException: ("Error connecting to host '%s:%s' - %s - retry %s/%s", '1', 22, 'Network is unreachable', 3, 3)
  </code></pre>
  
  <p>and</p>
  
  <pre><code>OSError: [Errno 101] Network is unreachable
  </code></pre>
  
  <p>If I use SSHClient(), it works fine. So, I don't understand why it won't work with the ParallelSSHClient(). Can anybody help?</p>