I just deployed my first stack of mobility switches over the weekend and am having a recurring issue with ports error disabling because the MAC limit I set (to 1) is being exceeded. I don't have any reason to believe that multiple devices are somehow connected to switchports via other switches/hubs/etc resulting in the port error-disabling. In the logs, I'll see an STP change and then a message about the interface shutting down:
Oct 22 22:31:43 :340001: <WARN> |l2m| changing the instance 220 port GE1/0/18 state from FORWARDING to DISCARDING
Oct 22 22:31:43 :128002: <ERRS> |l2m| MAC limit exceeded on interface gigabitethernet1/0/18, shutting down interface
It would seem that the two are related, but I'm not sure how.
I'm also seeing a ton of the following STP messages logged prior to the port being error-disabled and don't know if they're related:
Oct 19 19:45:29 :340004: <WARN> |l2m| Flushing mac-addresses on GE1/0/18 vlan-id 1 due to STP topology change
Any thoughts?