shutting RSTP Alternate blocked port and removing vlan from trunk

[info@]

Hi all

I need to clarify two things because most of the times I dealt with rstp
was when FWD ports went down and backup port transitioning to FWD in a full
logical loop topology

Can someone please confirm if my understanding is correct for two
situations below.

- Shutdown a port which is currently in  Altn BLK. This will trigger TCN
BPDU. And as a result root bridge will send configuration BPDUs with the
topology change (TC) bit set causing all the switches in the topology to
reduce the mac address ageing time to 15 sec?. Nothing else will happen.
-  If a Root FWD port is shutdown which is not part of logical loop. As
there is no Altn BLK port on that non loop topology, nothing will happen
except mac address ageing reduced on all the switches connecting to the
root bridge.

Thanks