Thanks Melissa for responding I was trying to play with physdev. Ignoring all the inbound stuff, if I was on the console of this machine (Mybox) MyBox +-----br0----+ | | router<--->eth0+ +eth1<--->Lan Where br0, eth0 and eth1 had no ip address, and I wanted to "yum update" (which I presume uses port 80) what rules would I need to put in place ? I was looking for something to do with 127.0.0.1 (the lo interface) and eth0. If I got that to work, the squid proxy should automatically follow, no ? Julian Melissa Meyer wrote: > > In the 2.6 kernel, there's an iptables module called physdev to match > the bridge's physical in and out devices so something like: > > iptables -A FORWARD -m physdev -p tcp --dport 25 > --physdev-in eth0 -j ACCEPT > > to allow smtp traffic through. > > > Julian Lyndon-Smith wrote: >> I want to be able to install a box that is a transparent bridge, but >> that is also running a transparent proxy, but with a twist .. >> >> i am a newbie in all things linux, so bear with me :) >> >> So far I have managed to install centos 4.3, and following various >> guides on the net, created a bridge between eth1 (connected to lan) and >> eth0 (connected to router). That works great. >> >> I also managed to install squid, get it running transparently and added >> a rule to iptables to make all that work just fine. So now, all my >> clients attached to the lan run through the squid proxy without them >> knowing. >> >> Now, for the twist. For development and testing, I assigned an ip >> address and gateway to the bridge. I need to be able for a "non-it" >> person to install this box without having to set it up at all , so it >> cannot have an ip address assigned, as it *may* be in use somewhere else >> on the lan or router. >> >> So, I changed the ip address to 0.0.0.0. Everything except squid still >> worked. I presume that's because it does not know how to route the data >> to get stuff. >> >> Can I add a rule to iptables or something to say "anything that's come >> from eth1 into the local box, after processing send to eth0" and >> vice-versa ? >> >> Julian. >> _______________________________________________ >> Bridge mailing list >> Bridge at lists.osdl.org >> https://lists.osdl.org/mailman/listinfo/bridge >> > _______________________________________________ > Bridge mailing list > Bridge at lists.osdl.org > https://lists.osdl.org/mailman/listinfo/bridge > >