IPTables Newbie

[gbburkhardt at aaahawk.com (Glenn Burkhardt)]

> I'm building an RH9 firewall/mailserver combo box for a small client.  =
> Sendmail appears to be running correctly in that I'm able to telnet to =
> port 25 from an internal system.  However, after performing the =
> following commands, I'm unable to telnet to the same port from and =
> external IP:
> 
> IPTABLES -A INPUT -p tcp --dport 25 -j ACCEPT
> IPTABLES -A INPUT -p ucp --dport 25 -j ACCEPT

Wouldn't have a clue about iptables commands - I use 'Shorewall'; it's all 
nicely laid out, and easy to configure.

I've also switched from Sendmail to Postfix; it's configuration is also much 
more straight forward.