[NTLUG:Discuss] services

[Richard Cobbe]

Scott Walters wrote on 12-14-1999:

> This is what I am trying to do.
> http://support.microsoft.com/support/kb/articles/q159/0/31.asp
> this is a link to a support page that says which tcp ports must
> be open on a firewall.
> 
> I am using linux as a firewall and would like to open these
> specific ports up.  Since there is a range of them I don't know
> how to do that.

You don't need to mess with /etc/services at all -- just specify the ports
numerically:

ipchains -A input -p tcp -d <LOCALIP> 28800:29000 -j ACCEPT
ipchains -A input -p tcp -d <LOCALIP> 6667 -j ACCEPT

See the ipchains manpage and documentation for more details.  Also note
that these rules will, of course, have to be put into your chains BEFORE
you deny/reject packets arriving on these ports.

Richard