Spanning-Tree

[Cyril Robert]

Hello

I have problem with the spanning-tree.
See the architecture in the attached files.
When i disable the trunk2, the spanning-tree doesn't work. But if i disable the port 21 (vlan6) and the port 22 (vlan7), the spanning-tree work.
Have you an idea ?
Thank you

[Mohammed Faiz]

Hi,

Are you running MSTP or just RSTP?

[Cyril Robert]

I running MSTP

[Richard Brodie_1]

There isn't really enough information on the MSTP configuration parameters to tell exactly.

However, unless it's really necessary (e.g. for security) I would have all the VLANs on all the links between switches. Manage load balancing with the instance tree priorities.

Suppose you start with where you ended up, with no direction connection between switch 1 and switch 3. Everything works fine.

Now you connect Vlan 6, so you have a loop. What MSTP might do, is to block the link between switch 2 and switch 4. Now you have connectivity on Vlan 6 only.

[Cyril Robert]

It's true ! Thank you !