Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Two SGE2000 in Stack and MSTP


I have Blade Server and Blade Switches from Fujitsu-Siemens. Two Blade Switches are configured with port channel/trunk (2 ports on everyswitch in port-channel/trunk and then interconnected) and MSTP. They are functioning very well. Few days ago I got two SGE2000 switches and connected them in stack config and would like to make such configuration like in this picture :

Lets say "B" and "C" switches are mine blade switches. "A" would be mine SGE2000 stack. If I connect all of them this way and configure MSTP on every of them this does not work. As if the switches do not support MSTP and network traffic overall just "dies" as if there were some kind of broadcast storm. Am I missing something ? What should I do ?

Best regards


Re: Two SGE2000 in Stack and MSTP

Hello Sir,

I believe you might do best by calling our support.  Here is a link:

If you want to check into this a little more, there here are a few thoughts.

The switches do support MSTP.  Have you checked for which switch is the root, do all switches agree?  You also need to make sure all the configs are the same, native VLANs and allowed VLANs, instance IDs and vlan ranges, etc ...

A "broadcast storm" sounds like you have introduced a loop into the network, all the lights come on, and your network looks like a Christmas Tree. Is this what is happening?  If the traffic simply dies, then this might indicate a port mismatch of some kind and the port is getting shut down by either system.  Having ports shut down for mismatches is fairly common.

I would suggest placing these switches into your environment one at a time, and then watching to see which switch introduces the problem.   Check the configs and make sure everything is compatible.

I would also suggest a call to our support center, as they might be able to answer your questions while you are adding the switches.


Andrew Lissitz

CreatePlease to create content