spanning tree

[stieven struyf]

We have (rapid) spanning tree running on a part of our network. Every few hours it recalculates.
Is this normal?
The resulting spanning tree topo is always the same, in the logs i can't find any reason(like plugged/unplugged ports).
I already upgraded to the latest firmware on all switches.
This network part has 2 3400cl's as core and multiple 2848 at the edge.

[Jason Luckett]

Hi Stieven,

Do you have any Trunks defined ??

I would look into the LACP configuration as this can Block and unblock ports as well.

Also have you set Spanning tree Priorities for the root switch and edge switches.

If you have not set the Root switch to priority 1 and all others to priority 4, I would recommend doing that, also do you have any blade servers as the switches in these can make spanning tree to renegotiate.

I hope this helps.

Jase