Hi Friends,

At my office there was one Linux Router (RHEL-5), As per my windows admin said me the diagram of Linux Router,

1. One Public IP given by ISP + They have given extra 14 public IP's to use...

2. As ISP told to purchase one router to split the 14 IP's, but we not able to afford the amount to purchase router, So we have made one Linux machine as router

3. Linux router was having 3 Eth ports, 1st Connected direct public IP 2nd Connected Public IP (Which Extra 14 IP in that 1 IP) and 3rd connected to local LAN

Now the scenario is, We have got one IP (Payable) (Ex: 192.168.4.1) + They have given 14 Extra IP (Free IP)(Ex. 192.168.4.2 - .15) by using 1st public IP they have done routing for 14 IP's, This 14 IP we can use anywhere in the LAN, We can ping each Other + this router connected to one local IP (172.16.4.x). As my windows admin said that there were used some shorewall third party tool to built this router.

The problem is that now that linux router got problem, not able to recover, so we have to make same machine to use. As i never did routing so i dont have any knowledge regarding this,

Please help me on this scenario to build my New Linux Router.

Please give some steps in details: like how to install or how to configure the router etc...

Thanks and Regards,
Sandeep CC

Why not implement an actual router like a cisco box? I have been doing RHEL admin work for a few companies and never have to deal with networking beyond assigning an IP, setting up gateways and basic routing info for the connections to and from the server.

Trying to make a server act as a router can be done but it would be much easier to use the right tool for the job and get a hardware firewall to do this for you.

In order to use RHEL, I imagine you would first have to set ip4 forwarding, net.ipv4.ip_forward = 1, to be on in your /etc/sysctl.conf and then create a whole bunch of iptable jump rules for the different connections.