4108gl - connectivity issue

[Matthew Shuter]

I have a closet with two 4108gl switches (A & B), connected to the same 5300 switch (C) via gigabit fiber.

Switch A had a chassis software issue two weeks ago (on a Monday). Called Tech Support, walked through a couple things, they sent me a replacement switch (D) next day.
Replaced Switch A with Switch D that Friday of the week the problem occurred. Everything was working ok. 1 week goes by, no problems.
Last Friday, Switch D (the replacement one) started having problems. I can ping from the switch to any other switch in the lan/wan, and even to workstations in the lan/wan just fine.. but when I ping from the workstation to the switch, >95% failure rates.

4108 switches are configured the same, minus the ip address. they are on a vlan for that building. uplink ports are configured the same on each end.
Only difference I can see is that Switch B has os G.07.53, where the faulty switch, D, has G.07.50.

I recall a similar issue I had in the past, where I replaced the chassis of the switch, and that solved the problem, but am not quite sure it was the same symptoms. I currently do not have a spare chassis, as it has been used and I need to call support to replace it under warranty.

any thoughts? have not called support yet, going to replace the module with the mini-gbics in it, and even the mini-gbics.

Thanks.

[Matthew Shuter]

replaced 3slot module, no change
replaced mini-gbic, no change.
replaced mini-gbic in 5300, no change.

cant update the os via tftp - not able to receive from the tftp server.
cant update the os via serial - times out, even if transferring at 115200.

[Ron Kinner]

Some kind of loop that is running broadcast traffic around in circles and loading down the switch? Turn on Spanning Tree and see if things settle down.

Ron

[Matthew Shuter]

I've removed all of the modules, except for the 3slot with the fiber mini-gbic, and no change.

I have place two of the modules in the other switch, no issues with them...and then put in two standalone 24port switches to get the computers up and networked..

going to work with them in my office this week, and see if I can find anything... if not, will be calling support on Friday