comp.os.linux.networking

Hello,

I am fairly new at linux , so please bear with me.

I would like to setup a linux router consisting of three nics.

ETH0 = WAN
ETH1 = 10.100.x.x and 10.5.x.x
ETH2 = Connected to a Switch


I need to NAT only ip address with the range of 10.100.XXX out to ETH0
( WAN ) any other range like 10.5.xx etc needs to exit via ETH2 which
is connected to the rest of my LAN network. At the same time, granted
if this is possible, I need to add rules to block any incoming/
outgoing packets from entering/exiting via eth0 to enter the ETH2 NIC
card. ( basicly any NAT ip address cannot enter the ETH2 NIC into the
rest of the lan )



I believe I need to do this via IP tables and work with setting up
static routes. Do you guys recommend for me to setup a full blown
server with mandrake or redhat or download a router distro like IPcop
or smoothwall?

have any of you guys done this before? is it doable? how can I
proceed with it?

Please advise and many thanks for your input.