I have a few Linux boxes with two NICs on each of them 1 NIC is assigned to the 10.1.1.0/24 network the other NIC is assigned to the 10.1.6.0/24 network...
I have been detecting UDP Broadcast packets from the 10.1.6.0/24 NIC that are getting forwarded to the 10.1.1.0/24 network.... I want to have these packets dropped... I could actually drop all packets from 10.1.6.0/24 network to the 10.1.1.0/24 if need be... I dont want any routing or bridging between the NICs .... does anyone know how to set iptables to accomplish this....
I have tried adding lines to the /etc/sysconfig/iptables file like these:
-A FORWARD -i eth1 -o eth0 -s 192.168.6.0/24 -j DROP
-A INPUTCHAIN -i eth0 -s 192.168.6.0/24 -j DROP

I have been trying various sorts like the line above and still pick up the traffic... Are my lines correct ? have any better ideas ?

any advice would be GREATLY appreciated.

thx,
ryan

First off, 192.168.whatever is not relevant to your network. You should be using a 10.x.x.x address. Secondly, make sure ip forwarding is not enabled. Thirdly, the networks ARE physically separated, right?

Take a close look at the packets and see who is generating them. ip number and MAC address
You can use several tools for this, eg iptables -I FORWARD -o ethx -d 10.1.6.255 -j LOG
Check the network settings in those machines..
Broadcast packets aren't automatically passed, there needs to be a condition to make it happen, and this needs to be corrected.. rather than plugging the leak, fix it.