router

[rajaneesh]

how to configure linux as arouter

[Irithori]

with route, ipconfig, ip, iptables, etc

[ni_boy]

If you're looking for more than a firewall and static routing or if you just want an easy web based interface you could look at vyata. Fully featured router/firewall, based on linux and will load on most x86 hardware.

[kapsikum]

for a normal linux desktop to be turned into a router, basic steps involved are:
1. turn on ip forwarding
this is your variable to check /proc/sys/net/ipv4/ip_forward. Set it to 1 to enable and 0 for disable.
2. decide which interface will be used for what, i mean which will be the LAN
and which will be the wan side.
3. Add a NAT rule to source nat the forwarded packets leaving from your wan side. Check out iptable tutorial 1.2.2 source Natting rules. Also make sure that the firewall is not blocking any packets on the forward chain. It may be the case if its a fedora/redhat host. For ubuntu, it may not be an issue.
4. Check out the routes and the dns resolver is doing fine.
5 Connect a host on the lan side of is box (the potential router) and try pinning (set the default route to point to the LAN IP of the potential router)
1. the lan interface of the router
2. wan interface of the router
3. some external IP say google or yahoo

Thats it.

[yunusemre]

I had done a project like this at university several years ago. I had plugged three ethernet cards on a linux machine. For exampe if i would have two networks which must communicate each other ,A and B. Two of ethernet cards for A and B networks. I routed network traffic from A to B as Irithori said with route, ipconfig commands...