[ILUG] weird FTP problem

[Lars Hecking]

> just wondering if anyone can help me with the following. When I
> try to ftp to a DEC Alpha in college I  can login grand, but when I do an ls or get or a put etc I get an error message. I can telnet into the machine grand, and I can also use FTP with many Irish ISPs successfully.

 Max. 72 columns per line are considered netiquette.

> Here is what I mean:
> 
> ---------------------------
> ftp> open alf2.tcd.ie
> Connected to alf2.tcd.ie.
> 220 alf2.tcd.ie FTP server (Version wu-2.5.0(1) Tue Sep 14 11:02:20 BST 1999) ready.
> 331 Password required for sammonm.
> 230 User sammonm logged in.
> Remote system type is UNIX.
> Using binary mode to transfer files.
> ftp> ls
> 200 PORT command successful.
> 
> 425 Can't build data connection: Connection timed out.
[...]

> ------------------------------------
> Could the problem be something to do with the following message I received a few weeks ago:
> ---
> Trying to connect to alf2.tcd.ie...
> Password required for sammonm.
> Sorry, your site 212.2.189.78 doesn't appear to have a proper nameserver
> setup.  [A reverse lookup on your IP address failed.]
> Login incorrect.
 
 I don't think this has anything to do with it. Normally, if a site
 requires reverse lookups for login/ftp, they won't let you in in the
 first place if the lookup fails.

 Could it be that there's a firewall (proxy, router, whatever)
 involved that blocks tcp port 20? Or, that ftp-data is disabled
 in /etc/services? All of this at the College end, I presume, if
 you can ftp ok to other sites.