Rapid spanning tree - slow convergence

[rjuchta]

Hello,

We have the following problem regarding to rapid-PVST operation:

We have impression that switches with configured rapid-PVST (spanning-tree mode rapid-pvst) still converge slowly, using PVST+ timers.

What could cause such behavior? Is it true, that when you have at least one switch that do not support rapid-PVST (only PVST+), entire STP instance

will converge using PVST+ timers? What commands/debug's would be best to resolve rapid-PVST issues?

Thanks,

WM

[Dan-Ciprian Cicioiu]

Hi ,

What does make you think that RPVST converge slowly ?

I think that one issue could be the edge ports. If you have PC/Routers/edge access ports you should configure them as portfast. This way if the topology will change will not affect those ports.

Dan

[viswamin]

Hi,

 Is it true, that when you have at least one switch that do not support rapid-PVST (only PVST+), entire STP instance
will converge using PVST+ timers? What commands/debug's would be best to resolve rapid-PVST issues?
Thanks,
WM

The answer is No.

If a RSTP switch connects to an STP switch, the RSTP switch will drop down to STP convergence speeds on a per-port basis

-Vijay