topic Re: FTP between RH 7.2 and MPE 6.0 in Operating System - Linux

FTP between RH 7.2 and MPE 6.0

dan dobbs — Thu, 06 Jun 2002 20:27:57 GMT

Greetings! I'm trying to get a file from my HP/3000 via my Red Hat box. I can ftp to the HP/3000, log in, and change directories, but when I try to 'get' a file I receive this message: "ftp> get SLIFLAT
local: SLIFLAT remote: SLIFLAT

502 PASV command not implemented by this server.

Passive mode refused."

I can ftp between my MPE and HP/Ux boxes without any problem. Ideas?

Thanks!

-dd

Re: FTP between RH 7.2 and MPE 6.0

dan dobbs — Thu, 06 Jun 2002 20:31:26 GMT

Sorry, never mind. Looks like all I have to do is type 'passive'. My apologies.

-dd

Re: FTP between RH 7.2 and MPE 6.0

Kodjo Agbenu — Fri, 07 Jun 2002 01:05:07 GMT

Hello Dan,

It seems that you found the answer by yourself.

In fact, with the FTP protocol, 2 connections are opened :

- the first one is used for commands (open, user, cd, pwd...). It goes from the FTP client to the FTP server on port 21.

- The second one is used for data exchange (dir, get, put...). It goes from the FTP server to the FTP client on port 20.

It is not generally a good idea, from the security point of view, to open connection from the FTP server to your client. Imagine what could happen if your FTP client had security flaws...

Therefore, the passive mode is another implementation of the FTP protocol, that makes both command and data connections to be opened from client to server.

Just a remark : generally, firewalls are configured so that ONLY passive mode can be allowed.

Good luck.

Kodjo