How to add 3rd NIC card

Dear All

I have redhat linux 9 , alrdy have two ethernet cards one is connecting to my internet gateway and otherone is connecting to my LAN. I want to add one more NIC, after fixing the working lan card into PCI slot , linux server detecting this new hardware, and i am configuring the same. But in network devices couldn’t find eth2 ( eth0 – Lan, eth1- internet gateway). If i try to add manually also it’s not getting activated… but in hardware list i am able to see the 3rd NIC card.

So i understood card is getting detected and configured, but i am not able to see eth2 anyware…. as i want to configure static routing for one more network.

Can anyone help me

Thanks in advance

Sakthi