title: why is pysftp connection not sending files? hanging on 'put'
body: <p>I'm trying to send some files via pysftp, authentication seems fine, but actually putting the file results in it hanging, doing nothing. The files are small (&lt;200kb) so I don't believe it's an upload issue (internet access is fine). Eventually the connection times out.</p>
  
  <p>Code:</p>
  
  <pre><code>if os.listdir(ftp_path):# only do if files are there
      with pysftp.Connection(FTP_SERVER,
                               port=FTP_PORT
                               username=FTP_USER, 
                               private_key=FTP_SSH_PRIVATE_KEY_PATH
      ) as sftp:
          with sftp.cd(FTP_REMOTE_FOLDER):
              for f in os.listdir(ftp_path):
                  if os.path.isfile(os.path.join(ftp_path,f)) :
                      # upload image to server
                      self.log.info("HB FTP, Start upload: "+f)
                      print(ftp_path+"\\"+f)
                      sftp.put(os.path.join(ftp_path,f))
                      self.log.info("HB FTP, Finished Upload: "+f)
  </code></pre>
  
  <p>Logging output here:</p>
  
  <pre><code>FSW_COMMS paramiko.transport 01/24/2015 04:23:58 PM: INFO: Authentication (publickey) successful!
  FSW_COMMS paramiko.transport 01/24/2015 04:23:58 PM: DEBUG: [chan 1] Max packet in: 32768 bytes
  FSW_COMMS paramiko.transport 01/24/2015 04:23:58 PM: DEBUG: [chan 1] Max packet out: 0 bytes
  FSW_COMMS paramiko.transport 01/24/2015 04:23:58 PM: DEBUG: Secsh channel 1 opened.
  FSW_COMMS paramiko.transport 01/24/2015 04:23:58 PM: DEBUG: [chan 1] Sesch channel 1 request ok
  FSW_COMMS paramiko.transport.sftp 01/24/2015 04:23:58 PM: INFO: [chan 1] Opened sftp connection (server version 3)
  FSW_COMMS paramiko.transport.sftp 01/24/2015 04:23:58 PM: DEBUG: [chan 1] normalize('.')
  FSW_COMMS paramiko.transport.sftp 01/24/2015 04:23:58 PM: DEBUG: [chan 1] stat('files')
  FSW_COMMS paramiko.transport.sftp 01/24/2015 04:23:58 PM: DEBUG: [chan 1] normalize('files')
  FSW_COMMS root 01/24/2015 04:23:58 PM: INFO: HB FTP, Start upload: 2015-01-17-19-37-07.jpg
  FSW_COMMS paramiko.transport.sftp 01/24/2015 04:23:58 PM: DEBUG: [chan 1] open('/files/2015-01-17-19-37-07.jpg', 'wb')
  FSW_COMMS paramiko.transport.sftp 01/24/2015 04:23:58 PM: DEBUG: [chan 1] open('/files/2015-01-17-19-37-07.jpg', 'wb') -&gt; 34613039393262343666383036653839
  </code></pre>
  
  <p>Any help or pointers on how to debug further much appreciated,</p>
  
  <p>Jules</p>