Spanning Tree Question

[PhilUK]

Hello,

I have 7 3400cl switches running RSTP.  Two are used as the core and have the spanning tree priorities set to 0 and 8192.  The rest are used as edge switches and have the default priority of 32768.

I need to attach 2 new 2530 edge switches back to the core which also have the default priority 32768 but these run MSTP.

Do these new switches need to be changed to RSTP or is MSTP fine to connect to the existing switches?  Will STP reconverge when I power them up causing a brief outage or does that only occur when the root switch changes?  I have attached a diagram to show the connections.

I'd appreciate any help on this.

Thanks

Phil

[Richard Litchfield]

ProCurve switches are shipped with spanning tree disabled - so they would not cause any convergence if no changes are made.

You should try and keep spanning tree versions consistent; you can certaily end up with problems. With MSTP though, everything goes into instance 0 or CST by default. You may want to at least make the priorities higher than default (ie larger number than 8 --> 32768).