Ping stops after exactly 10 minutes.

[Control Freq]

Hi,
I have posted here before regarding an intermittent ping problem.

I have managed to some more testing at my clients site, and I have
identified a clear pattern to a problem.
I have a Windows 200 Server, and an XP Embedded touch screen computer,
networked through a 3COM Hub.

Both machines have static IP addresses, and are on the same subnet.

Now, I start a 'ping -t 192.168.1.X' from each machine to the other,
and leave it running.
The ping responses at this point are good.

After EXACTLY 10 minutes, the ping responses, from both machines,
change to 'request timed out'.

If I now wait another 10 minutes, EXACTLY, the ping responses will
come back good again.

During the intervening time I am doing nothing on either machine.

So, what could cause the network to drop out at regular 10 minute
intervals?

I cannot work out if the problem is with the XP Embedded touch screen,
or the Windows 2000 Server PC (or both).

Any suggestions?

Someone has suggested looking at the ARP table, but I didn't think of
that, I will try looking at that on my next visit to the clients site.

Regards

 

[Control Freq]

Hi, does anyone know if the arp cache might be being cleared on a 10
minute interval? Or the Win 2K Server might be sending some
instruction to clear the ARP cache of XP embedded machines?

Any suggestions appreciated.


Regards

 

[Control Freq]

Hi, well I discovered that the ARP Cache is getting corrupted. I don't
know what causes it, but 'arp -a' shows a list of MAC and IP
addresses, and after exactly 10 minutes I see that some of the MAC
addresses are appearing in the list twice! for different IP addresses.
There doesn't seem to be a pattern to it, other than it happening
every ten minutes.

This will DEFINATELY cause a problem with TCP/IP comms.

I can refresh the list, and add static arp entries using 'arp -s ....'
and this fixes the issue. But it doesn't answer the causes though!


Thanks anyway.