Hi-
I occasionally see a few 5GHz get caught in a 'churning' state whereby ARM flips them back and forth between a channel pair. In this case, I've got 20MHz channels in place; and ARM flipped between channels 165/161 for a few hours.
It always left 165 to go to 161 because "Empty Channel"
Within 60 seconds, it would leave 161 due to "Error Threshold". It would place it back on 165.
Lather, rinse, repeat every 5-10 minutes for a couple of hours.
Has anyone else seen such behavior? I would think the Error Threshold would be reached due to high noise floor, interference or channel utilization - but it's not clear to me why ARM would think the 'bad' channel to be considered 'Empty'. Does ARM strictly consider 'Empty' to mean no known RF neighbors on that channel (irrespectiive of interference sources) and/or simply evaluates noise floor?
This is happening on AP-135s on 6.4.2.3. I've been having this issue for a while though (read: including previous versions). No clients connected at the time; but as a point of reference: client match enabled; client aware enabled; Min/Max TX 6dB apart; Channel Qual Aware ARM disabled. US Reg Domain. DFS channels disabled [36-48/149-165].