Using SSH to set up a secure ftp connection to Duke Statistics

• NOTE: you must use an ftp capable of passive transfers (see partial list below)
• To establish the port forwarding, make an ssh connection to isdsmachine from remote as follows

    
  remote% ssh -L5021:isdsmachine:21 -L5020:isdsmachine:20 isdsmachine
  

  where
  • isdsmachine is the replaced by the name of the Duke Statistics machine with which you want to transfer files
  • remote is the non-Duke Statistics machine from which you are connecting
• In a separate window on remote

    
  remote% ftp localhost 5021
  220 isdsmachine FTP server (Digital UNIX Version 5.60) ready.
  Name (localhost:user): 
  331 Password required for user.
  Password:
  230 User user logged in.
  Remote system type is UNIX.
  Using binary mode to transfer files.
  ftp> passive
  Passive mode on.
  

• List of known passive ftp clients
  • Netscape may be used for both downloading and uploading files, by opening a connection ALT+L and entering:

    ftp://username@localhost:5021/
    

    For example, if your Duke Statistics login is jimbo and your home directory is /usr/home/jimbo

    ftp://jimbo@localhost/usr/home/jimbo
    

    • To download a file, click on it
    • To upload a file, select Upload file option from the the File menu.

  • FreeBSD supports passive ftp a number of ways:  pftp, ftp -p, or by typing passive at the ftp› prompt
  • Linux supports passive ftp via the   pftp command
  • Unfortunately, neither Digital Unix nor Solaris ftp command line clients support passive transfers, so use Nestcape.