Firewall

[Benjamin J. Weiss]

On 24 Sep 2004, Damien Estrada wrote:

> Can anybody tell me how to unblock port 25 from the firewall installed
> with red hat ??
> 

The file that you need to edit is /etc/sysconfig/iptables.  do a 'man 
iptables' without the quotes to get an idea of the options, or go into the 
file, make a copy of one of the lines that allows in a port that you want 
(such as port 80, for web or port 22, for ssh) and then alter the port 
number to 25.  Once you've edited the iptables file, you'll need to do a 
'service iptables restart', again, without the quotes, as root.

Note, however, that there's more to getting your email server to accept 
external email than just unblocking the port.  RedHat now installs in such 
a way that the email server (sendmail, by default) will not accept email 
from external sources.  This is a security feature.  If you need to know 
how to configure your email server to proerly receive email without 
becoming an open relay, there are some good references at:

http://www.redhat.com/docs/manuals/enterprise

HTH,

Ben