I have a scenario of six switches (C2960S, Version 12.2) running out of PVST instances so a transition to MST is inevitable. Seeing how small scale the setup is, I assume I could shut a few links to ensure there are no loops, turn off spanning-tree and then configure MST.
Once done I should be able 'no shut' the shutted links. Am I right in it being this straight forward, or are there any caveats with my approach?
UPDATE 1: I did convert the root bridge, after shutting enough links to not have a ring/loop, to mst using the following configuration:
#spanning-tree mst configuration
#instance 1 vlan 1-1024
#spanning-tree mode mst
After this I lost connection between the root bridge and a neighbor switch. The state of the port was BKN. I proceeded to check all trunks native vlans, but couldn't find a mismatch. I quickly reverted and here I am, with not much more information.
UPDATED QUESTION 1: Given the simple topology, if I disable enough links to prevent the ring and thus loops, could I not disable stp altogether and then set up mst on a switch at a time?