MST obsoletes spanning tree portfast ?

[globalnettech]

Hello experts,

I have been told that implementing MST does make the use of spanning-tree portfast unnecessary. As far as I can see, even after configuring MST, the forward delay and maxage timers are still the same as with PVST, that is, 15 and 20 seconds, respectively. Can anybody clarify ?

Thanks a bunch in advance.

GNT

[andrew.burns]

Hi,

First off, make sure you don't confuse MST (802.1s) with RSTP (802.1w) as MST enables RSTP but the reverse isn't true. Portfast is still used in the Cisco implementation of RSTP to configure "edge ports", i.e. portfast is more relevant to RSTP - not MST.

You are correct in that the forward delay/maxage timers don't change after implementing RSTP - but they are only there as a backup and not used in normal RSTP operation.

HTH

Andrew.

[globalnettech]

Hello Andrew,

great, thanks for the background information.

Regards,

GNT