Tugger the SLUGger!SLUG Mailing List Archives

[SLUG] Ipforwarding

Hey all,

I have ipmasqadm working well with my setup at home and so on but I have one

My linux firewall is on 200.xxx.xxx.200 and I have routes for
200.xxx.xxx.201 to go to the this firewall. The linux box has a rule for the
201 address be a port forward for port 80 to an internal machine using the
below command:

/usr/sbin/ipmasqadm portfw -a -P tcp -L 200.xxx.xxx.201 80 -R 80

this is so the outside IP address for 200.xxx.xxx.201:80 goes to an internal
machines web server.

Now what I would like to confirm is how does the firewall IP forward the
internal webservers internal IP back out via the external address and not
the external address of the firewall... eg.. go out as 200.xxx.xxx.201 and
not as 200.xxx.xxx.200

I have the feeling (haven't been able to check) that the internal machine is
masqueraded as the firewalls IP and not the webservers external IP..

Can somebody guide me on how to ipchain this to it's correct rule..??

George Vieira
Network Administrator
Citadel Computer Systems P/L