[KLUG Members] Firewall rules

[Jeremy Leonard]

I'd like to redirect all traffic from my local network headed for the 
public side of my firewall back to the private address of my firewall.

Users when on the net have no trouble connecting to services I provide. 
IMAP WWW FTP.
However, when they are on site with their laptops they can't because the 
dns server returns the public address of my services. I only have one 
server and only want one server. This one server is my firewall, dns, 
dhcp, samba, ftp, mail(smtp,IMAP), and ldap.

For computers that don't leave the lan I set a host file with the 
correct local address for my domain.

Any pointers in configuration would be helpful.

Is there a way to configure DNS to respond with different address based 
on the interface the request was received on? Or run BIND twice on the 
same machine each using the appropriate interface?

Thanks,
Jeremy