Dual Network Help

Hi,

I have a Linux RT box at work. It has a four port NIC card. I have been trying to utilze Eth1 and Eth3 to communciate on two seperate networks. I have set the default gateway for Eth3 and can ping to the outside routers. I set a static gateway for Eth1 but can only ping the first gateway. I placed a sniffer to verify the ping requests are going out. The sniffer shows the pings going out and the replies are coming back to the Eth1 port, however that port is not recieving any IP traffic data. As a side note for Eth1 I am utilizing Multicast UDP traffic and Eth3 is just standard TCP traffic. Any help you can provide would be greatly appreciated. The following is my network which works fine with a windows box just not this Linux box.

Eth1
xxx.xxx.21.184 IP
xxx.xxx.21.177 gateway
xxx.xxx.21.191 broadcast
xxx.xxx.xxx.240 netmask

Eth3
xxx.xxx.72.21 IP
xxx.xxx.72.1 gateway
xxx.xxx.72.255 broadcast
xxx.xxx.xxx.255 netmask

two things..

1. when you say, "..I set a static gateway for Eth1 .." what was the exact command that you used?

2. are you running a firewall, or iptables? If so, be sure that both multicast and UDP traffic are being allowed back in.

cuervo