Hi Im a little perplexed by this situation I have centos 4.5 installed on 2 pcs - each with 2 network cards machine 1 eth0 Link encap:Ethernet HWaddr 00:14:2A:6B:C8:CC inet addr:10.54.7.2 Bcast:10.54.7.255 Mask:255.255.255.0 eth1 Link encap:Ethernet HWaddr 00:11:50:9B:A2:90 inet addr:10.54.0.2 Bcast:10.54.0.255 Mask:255.255.255.0 machine 2 eth0 Link encap:Ethernet HWaddr 00:14:2A:69:4C:47 inet addr:10.54.7.3 Bcast:10.54.7.255 Mask:255.255.255.0 eth1 Link encap:Ethernet HWaddr 00:11:50:9B:A5:0A inet addr:10.54.0.3 Bcast:10.54.0.255 Mask:255.255.255.0 machine 1 & 2 can ping each other on either subnets machine 3 (windows)... C:\>ipconfig Connection-specific DNS Suffix . : IP Address. . . . . . . . . . . . : 10.54.7.16 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 10.54.7.1 cant ping anything on the 10.54.0 subnet, nor does that subnet show up ip using a port scanner... C:\>ping 10.54.0.2 Pinging 10.54.0.2 with 32 bytes of data: Request timed out. Request timed out. C:\>ping 10.54.7.2 Pinging 10.54.7.2 with 32 bytes of data: Reply from 10.54.7.2: bytes=32 time<1ms TTL=64 Reply from 10.54.7.2: bytes=32 time<1ms TTL=64 Any ideas why this is happening? I dont have a firewall on the 10.54 address, Thanks Bob