Hello,
We have a situation where we have a single Catalyst 3850 switch that needs to be migrated from MST to Rapid-PVST. It is in the middle of transit traffic between Rapid-PVST switches.
Here is a "diagram" of the connectivity:
[Nexus 56128P (RPVST)]<-->[C3850 (MST)]<-->[C3750(RPVST)]
The switches are all connected with trunk links, and the Nexus 56128P is the "core" switch with priority 4096 for all VLANs. They are all electing the proper root, but obviously the C3850 is giving us issues with Root Port election due to its R/PVST imitations (there are other cross-connections not shown on the above diagram).
The customer is asking how much downtime they can expect when configuring the C3850 to utilize Rapid-PVST (enabling Rapid-PVST where it currently uses MST).
I am assuming that it would be a short downtime (sub 2 minutes) as the ports would need to go through the full forwarding process and negotiate P2P links with RPVST neighbors. Can anyone provide some insight into what kind of downtime we are expecting?
Thanks in advance