problem pinging on 255.255.254.0 subnet
 

I am having strange problem with a linux system on a network with 255.255.254.0 subnet mask. The network is comprised of IPs in the 10.10.0.0 and the 10.10.1.0 range. The linux box has an ip address of 10.10.0.110 and can ping any systems in the 10.10.0.0 range without issue. However, it cannot ping any system on the 10.10.1.0 range. The really stange thing is that systems on the 10.10.1.0 range can ping the linux machine without issue.

The linux box is a fresh install of CentOS 4.2 with available updates applied. The system can talk to the internet without issue.

Is there anything special I have to do to get this system functioning correctly?

Any information about where I could look for a problem would be extremely appreciated or if there is any further information I can provide to get assistance please let me know

Thanks

Have you checked to see if your firewall is responsible? Check the INPUT and OUTPUT chains.

Yes I did check that and I disabled the firewall completely to ensure that would not be the cause.

Thanks for your input

I am not a networking expert, but this does seem strange. Several things you might try/consider in no particular order:

1. Run tcpdump on your Linux box to see if the ping is actually going out and whether a response is coming back. If you have similar tools available on another machine on 10.10.1.0/24 do the same on it.
2. See if the command "ifconfig eth0" (substitute your interface for eth0) shows the values you expect, and see if it is showing any dropped packets
3. Check the routing table
4. Consider that the problem may be outside your Linux box. Can the other nodes on 10.10.0.0/24 ping 10.10.1.0/24 and vice versa?

That's all the ideas I have. Good luck.