Hi,

I have strange issue after updating SWOS to 2.12, where RSTP stops working and will switch ports to discarding.
I have first hit this issue back right after release of 2.12, but didn't have time to debug and just rolled it back.
So now I have updated only one of the switches, and should be able to investigate it in more detail.

Here's my current setup:
root - HAP ac2
sw1 - plugged into HAP ac2 (RB260GSP, swos 2.11)
sw2 - edge switch connected to sw1 (RB260GS, swos 2.12)

If I enable RSTP on the ports connecting SW1 and SW2 - it will detect as:
* on SW1: role: designated, type: point-to-point (instead of edge), state: discarding (periodically switches to forwarding and then back to discarding).
* on SW2: role: designated, type: edge (instead of root), state: forwarding

Port connecting both switches is set up as trunk port, settings are (same on both SW1 and SW2):
* VLAN tab: vlan mode=strict , receive=only tagged, default id=1, force id=off, egress vlan header=leave as is
* VLANs tab: IVL=on, IGMP snooping=off, mode=leave as is

On the system tab, "Allow from vlan" is set to management VLAN.

What can be interfering with RSTP here?
If I remember correctly, when I also upgraded SW1, it had similar issues with RSTP on the trunk port between the switch and HAP AC2 router, but I'm less confident about details there.