Port problem on 3425PWR-XL switch

[technology]

We are having a problem with a Compaq server connected to a C3524PWR-XL switch. Periodically, the switch looses connection to the server (or the server looses connection to the switch)

Typically, workstations on the same LAN segment can access (ping) the server, but workstations on different LAN segments or VLANs cannot. VLANs are routed through a 3640.

The switch is running 12.0(5.1)XW. The port on the switch and the NIC are configured for 100/Full.

I've found that if I shutdown the port and then no shut the port, the connection is re-established. Or, if I unload the NIC driver from the server and reload the drive, the connection is re-established.

I've tried replacing the NIC (Compaq and 3COM), replacing the cable, and upgrading the IOS on the switch (was 12.0(5)).

Any suggestions on where to look next?

Thanks!

Steve

[j.chenevey]

Did you enable portfast on the switch port? This bypasses a few STP states and places port in STP forwarding state automatically.

[mberrocal]

If you can ping the server from the same VLAN, then the switch isn't loosing connection to the server.

So the problem sounds more like a routing problem.

Try and do some traceroutes (with -d option in win2000) from the server to hosts on the other VLANs and vice versa.

Also check out a route print (if win2000) when the problem shows up.

post the traces and route print, if you need more help.

[technology]

Thanks for the suggestions.

I think I have determined that this is a problem coming in to the server from my 3640 router rather than the switch. Workstations on the same lan segment as the server do not loose their connection. Only workstation on remote segments of the network.

I have also found that if I do a 'clear arp' on the router the connection is re-established.

Now, I just have to figure out why. And find a way to fix the problem...

Steve