Greetings all. I am trying to build a firewall, and I am running into a little trouble, hope you can help.
What for: This firewall is to divide a section of my LAN from there other computers. The external addresses are in the 192.168... Range, the internal will be in the 10.0... Range. What I have: Pentium base with 2 3c509's. Most basic Potato install (no x, no dev, no nothing). What's wrong: The problem I continue to encounter is that the firewall will not allow traffic to flow through. Here are the steps I have taken. After initial install, I set up the second NIC in /etc/network/interfaces by adding address, netmask, etc. I then restarted the network (etc/init.d/networking restart), with no errors. I then changed the ipforward flag in /etc/network/options from no to yes, restart network again. To make sure it worked I checked (more /proc/sys/net/ipv4/ip_forward) with a return of 1. At this point, the primary NIC is connected to external network, working (tested with ping), but a test box (win 2k, setup with firewall as gateway) on the 2nd internal NIC can not ping the firewall and can not be pinged by the firewall. I tried flushing the ip_chains rules and making INPUT OUTPUT and FORWARD all ACCEPT and nothing else, no luck. I tried installing ipmasq (which I want to use once things are working anyway) but also no luck. Does anyone have any suggestions? Thanks, -Tom
