Supernetting and Gateway question

One of our customers is experiencing some issues with supernetting and connecting a PC to one of our products (DB8).

The Network settings of the PC are:
IP: 192.168.62.6
Mask: 255.255.254.0
GW: 192.168.63.254

Network settings of DB8:
IP: 192.168.62.61
Mask: 255.255.254.0
GW: 192.168.62.254 (can ping this device from the PC) 192.168.63.254 (can't ping this device)

Both devices are connected to the same physical 48 port HP Procurve switch.

Shouldn't the device (DB8) just ignore the GW address as the third octet in the IP address is the same? If not, then I can supply some more information, but for now I'll try to keep it simple.

Kim Rechnagel

The GW on the PC is different than whats on the DB8. Thats not a typical setup. The GW is the router that connect the LAN to outside/internet/other networks.

Sounds like it's just a typo, try setting the GW on the PC to 192.168.62.254

Yes I know that the gateways are different, but as the two computers are on the same subnet, shouldn't the PC and the DB8 just ignore the gateway address, no matter what the gateway is?

Furthermore, if you take a closer look you'll see that if the GWs are the same on the two devices then I can't ping the DB8.

The DB8 is running Windows NT Embedded and I guess that the TCP/IP protocol in this old build may not support suppernetting?

I would still like to get some input regarding my original question also. (Shouldn't two computers on the same subnet ignore the GW address when communicating?)

Kim Rechnagel

Yes I know that the gateways are different, but as the two computers are on the same subnet, shouldn't the PC and the DB8 just ignore the gateway address, no matter what the gateway is?

Yes, the PC should ignore the gateway when it tries to connect to your DB8. I was just making sure that you placed different gateways intentionaly. The question did not sound like an experiment.

Furthermore, if you take a closer look you'll see that if the GWs are the same on the two devices then I can't ping the DB8.

This makes your question clear. So when you put the correct GW (192.168.63.254) in the DB8, PC cant ping it. Hmm, The only thing I can think of now is mistyped mask is DB8. But even that should not affect local subnet communication unless there is a bug in DB8's WinNT

The DB8 is running Windows NT Embedded and I guess that the TCP/IP protocol in this old build may not support suppernetting?

Not sure about that.

I would still like to get some input regarding my original question also. (Shouldn't two computers on the same subnet ignore the GW address when communicating?)

Again, Yes.

Tell ya what... if possible, try temporarily removing the GW from both devices. I wonder.

Thanks a lot for you answers Ammar. I'll ask the customer to leave out the GW and see if it makes any difference.

Kim