Cisco Nexus 3000 Series Configuration Manual page 128

Generating Syslog Error Messages
Number of MAC Addresses added: 944088
Number of MAC Addresses moved: 265
Number of MAC Addresses removed: 943920
The MAC address moves are also logged with a minimum logging level of six that is required to display
which MAC addresses move:
2016 Jun 12 16:05:31.564 switch %FWM-6-MAC_MOVE_NOTIFICATION:
Host 0000.0000.fe00 in vlan 85 is flapping between
port Eth104/1/8 and port Eth104/1/9
What to Do Next
Check for correct STP convergence and for STP port-states across all the switches in the topology. Confirm
that there are no disputes or incorrect port states.
If the source of the data frames that are physically moving is identified, control the source in order to halt the
rapid and continuous moves.
By default, dynamic learning is reenabled after 180 seconds. At that point, any STP disputes or inconsistencies
should be resolved. If not, the dynamic learning is disabled again.
Cisco Nexus 3000 Series NX-OS Layer 2 Switching Configuration Guide, Release 6.x
118
Configuring STP Extensions
OL-29545-03