MAC addresses constantly Deleted and Added

[sebastian.lemke]

Hi,

I am experiencing a strange behaviour on a WS-C2960X-24TS-L running c2960x-universalk9-mz.150-2a.EX5.bin.

MAC addresses are constantly deleted and Added on one port. I configured the following:

mac address-table notification change interval 10
mac address-table notification change history-size 200
mac address-table notification change

interface GigabitEthernet1/0/24

 snmp trap mac-notification change added
 snmp trap mac-notification change removed

The MAC address aging time is set to 300 s. When issuing a "show mac address-table notification change" I can see a number of MAC addresses being deleted and added every few seconds on the interface Gi1/0/24. The MAC addresses are not learned on any other port. Most of the time they don't appear in the output of a "show mac address-table". Only when constantly issuing this command i sometimes hit a moment where the MAC address is allocated to the interface Gi1/0/24.

Anybody a hint why this is happening?

[dbergman13]

Ports were stable. Tried different cables. No redundant paths. I had two additional devices have the same issue recently. These were HVAC devices that were working fine for about a year and the only way to get them back online was to statically add the mac address on the switch. We have about 54 different devices in total now with this issue.