Fiber Modules

[mense23]

How many fiber modules can you have in a stack?
I have 3 3c16980 switches connected with a Matrix Module.
Since the beginning I have also had a 3c16975 (1000MB) fiber module installed. This weekend I install another 3c16975 in the last switch. I have had some disconnect problems with my clients since then. The new fiber module only has another 3com switch on the other end.

 

[ADB100]

There shouldn't be any problems. A couple of things to check with:

1. Duplex settings on the Fibre link - make sure they are the same either end.
2. Software revisions - I would ensure all the switches are running 2.70 (the latest) in case there are any issues with newer firmware on the 1000BaseX module.
3. How big is your network - you haven't just connected 2 big broadcast domains together and its just too big for the switches to handle (too many MAC addresses)?
4. Loops in the network - Have you created a loop in the network by connecting this switch? Is STP enabled etc

Andy

 

[TreyJ]

From what I've seen with Gigabit Ethernet interfaces, they need to be set to autonegotiate.

 

[mense23]

The 3rd switch in the stack seems to be having the problem with the fiber module. I have since removed the fiber module and my clients PC have been running fine. I am not using the new fiber connection at this point in time.
I plan on upgrading the Firmware to 2.70 this weekend.