I have a RaQ3 with multiple IP addresses assigned. I'd like to block Telnet access from all IP's except the primary IP. In fact, I'd like to block everything except HTTP/POP/SMTP ports to tighten up security a little...

Anybody know how to do this?

TIA
Dave.

Unless you want to use a firewall software, you can use TCP wrappers with the inetd server.

Take a look at this,
http://www.itworld.com/AppDev/1076/UIR000630tcp/
or this
http://freeos.com/articles/3729/

TCP wrappers will allow you to control anything that is ran via the inetd super server. Look in /etc/inetd.conf to see what services are started via inetd.

You can drop a line into your hosts.deny to block all traffic to the IPs of your choice and then allow POP traffic in. Sendmail and http traffic are not, by default, ran through the inetd server, so these will not be affected.