title: python paramiko SSHException: Channel closed
body: <p>Im trying to establish a sftp connection to remote ubuntu machine.I was able to establish ssh connection.but it throws me an exception at open_sftp()</p>
  
  <pre><code>import paramiko
  ssh = paramiko.SSHClient()
  ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
  ssh.connect(hostname=hostname,port=port,username=username,password=password)
  sftp = ssh.open_sftp()
  </code></pre>
  
  <p>paramiko.SSHException: Channel closed</p>
  
  <p>can anyone help me.thanks in advance.</p>