Some notes: Unless you are setting up box "b" to be a bridge, the interfaces should have address's on different ip networks (according to your diagram). Make eth0 192.168.1.x 255.255.255.0 and eth1 192.168.2.x 255.255.255.0. In /proc/sys/net/ipv4 there is a file called ip_forward. It should contain the number "1" if you want your box to forward packets (ie, route). To do this do the following: echo '1' > /proc/sys/net/ipv4/ip_forward Now, box a should know how to NAT/Masq for the 192.168.2.x network as well as the 192.168.1.x network. Also, on box A do a route to point the 192.168.2.x network through the ip address of the 192.168.1.x on box b. That way box A knows how to get to box C. Confused yet? -dallas ----- Original Message ----- From: "Eric" To: Sent: Wednesday, December 19, 2001 8:57 PM Subject: computer networkers, please rise > Hi, > > I'm gettin' jiggy with my home network, and I am getting myself wrapped > around the axle. Can you help? I'll make this as short as possible, > consistent with giving all necessary info: > > I have the following setup at home: > > > LAN WAN > > [HOST_C > (192.168.0.3/24)]--------------[HUB]------------[HOST_A_(192.168.0.1/24)(wit > h_DSL_CONNECTION)]-------------QWORST > > > > > Between HOST_C and the HUB, I want to insert HOST_B. At some point > hopefully, HOST_B will be a firewall; hence I need to get it to forward some > packets which is what I am testing now. HOST_B's name is "Lappy" and it is > a RedHat 7.1 Laptop with two PCMCIA slots, into which I have put two 3C59x > cards. I know how to configure an eth device. To get this setup here to > work, it seems as though I should just do it twice and then enable packet > forwarding; is this correct? That is what I tried initially, but it was all > down hill from there. > > When I insert HOST_B between HOST_C and HUB, several different problems > arise. Basically, instead of telling all the configurations/scenarios I > tried, it boils down to the fact that if I keep all hosts on 192.168.0.0, > either HOST_C can ping HOST_B and vice versa, but HOST_B cannot access the > Internet, *or* HOST_B can access the Internet, but HOST_C and HOST_B cannot > ping each other. A few times, I managed to get it so neither alternative > worked. Sometimes, in order to get functionality on eth0, I would have to > unplug eth1, etc. It seems like HOST_B gets confused when dealing with two > NIC's with a hosts on each side, and can only figure it out when one "side" > is removed from the picture. > > Alternatively, I tried making both HOST_C and eth0 on HOST_B be on their own > network (10.0.0.0), while keeping eth1 of HOST_B and HOST_A on 192.168.0.0, > but it just got worse. I can provide details if necessary, but there are so > many different combinations that my head is spinning. > > Let me say that I have enabled forwarding, and between HOST_C and HOST_B, I > was using a crossover cable, but between HOST_B and HUB, I was using a patch > cable. I have tested both of my PCMCIA slots, both my 3com cards, and > cables--all seems to work. I have rebooted at least 35 times today messing > with this and that, and I feel nauseous. I haven't felt this bad since the > last episode of Emeril. > > Could anyone start by telling me whether I should have two networks 10.0.0.0 > & 192.168.0.0, or keep everything on 192.168.0.0? Next, do I put two > entries in /etc/hosts, one for Lappy 10.0.0.1 and another for Lappy > 192.168.0.1? I don't know what else; can anyone help? > > Eric > > ________________________________________________ > See http://PLUG.phoenix.az.us/navigator-mail.shtml if your mail doesn't post to the list quickly and you use Netscape to write mail. > > PLUG-discuss mailing list - PLUG-discuss@lists.PLUG.phoenix.az.us > http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss