Cannot ping both NIC's!!

[Bruler]

I have two custom built servers. Each has two NIC's. On one of the servers I am able to ping both of the NIC's but on the other server I am only able to ping one of the NIC's

On the machine in question, both NIC's say they are connected, and when I disable the working NIC and use only the NIC that cant be pinged, i can still get out to the internet and see the network. So the NIC is working, but when I try to ping it, it times out. Does anyone have any suggestions on why this could be?

Thanks!

[Fleming]

This can be because there is a firewall in between somewhere. Failure to PING is 99% a firewall issue.