To all, I have found what appears to be an excellent article on this subject. I did not plan to use load balancing, but I am going to dig out an old machine and follow the directions in the article. For anyone else who is in a similar position here is the link:
http://www.samag.com/documents/s=1824/sam0201h/ It is from Sys Admin on redundant internet connections using linux. >Subject: RE: Dual Internet Connection >Date: Thu, 4 Jul 2002 17:03:30 +1000 > >iptables <> router > >It tracks connections and not which device it came from. You need iproute 2 >to do something like you need. > >I wonder what it would be like to have 2 default gateways and DROP packets >on each gateway depending on the source address.. wouldn't routes then try >the other link???? > >Say > >192.168.0.1 192.168.0.2 >| eth0 | >------------------- > FW >`add default gw 203.x.x.x` >`add default gw 210.x.x.x` >iptables -A FORWARD -s 192.168.0.1 -i eth1 -j DROP >iptables -A FORWARD -s 192.168.0.2 -i eth2 -j DROP >iptables -A POSTROUTING -s 192.168.0.1 -o eth2 -j MASQUERADE >iptables -A POSTROUTING -s 192.168.0.2 -o eth1 -j MASQUERADE >------------------- >|eth1 |eth2 >203.x.x.x 210.x.x.x > >Would Host Unreachable make the route try the other default >gateway??? Not a >pretty sight though..... >Sorry if it's a bit messed up.. I'm about to leave work..
