SunScreen 3.1 Administration Guide

FTP Proxy

To use the proxy and successfully make FTP connections through the Screen, you must FTP to the proxy on the Screen rather than directly to the end system. The Screen's policy rules will only allow FTP connections to and from the proxy.

For information on setting up the ftp proxy, see "PROXY_FTP".

To Use the FTP Proxy

The following example steps show what happens when a user wants to connect to the system named, which has an anonymous FTP account. To get there, they must first ftp to the SunScreen proxy named Screen.

Note -

The anonymous proxy user is prefigured during the installation of the software. It is an unauthenticated proxy user; as such, any string provided before the first @ ("at" sign) in the password is ignored. The password after the first@ (here: is the back-end user password--in this case, the user name as is customary usage for anonymous FTP.

  1. Type the command:

    % ftp screen

    The following text appears:

    Connected to screen
    220-Proxy: SunScreen FTP Proxy Version 3.1
    	: Username to be given as <proxy-user´@´<FTP-server-host>
    	: Password to be given as <proxy-password´@´<FTP-server-password>
    220 Ready
    Name (screen:zzz)

    The format for the username is the username and the destination server separated by an "at" sign.

  2. Type your password at the prompt to authenticate you to this proxy:

    331- Proxy: Authenticate & connect:
    331 Password needed to authenticate 'anonymous'.

    The password is not echoed. Its format is two passwords separated by an "at" sign: The first password is the password for the proxy and the second is the password for the destination ftp server, for example, anonymous is the password for the proxy and zzz@thereisnohelp is the email address that requires for anonymous ftp.

    The following text appears:

    230- Proxy:
    	: Authentication mapped ´anonymous´ to backend user ´anonymous´.
    	: Connecting to ( - done
    	: 220 FTP server (Version 2.0.9) ready
    	: 220-Welcome to Sun Microsystems Corporate FTP Server.
    	: 220-
    	: 220 ftp FTP server (ftpd Wed Oct 30 23:31:06 PST 1996) ready.
    Proxy: Login on server as ´anonymous´.
    Server:331 Guest login ok, send your e-mail address as password.
    Proxy supplying password to server
    230 Guest login ok, access restrictions apply.
    ftp> bye
    221- Proxy: Quitting service.
    221  Server: Goodbye.