The MAC move feature is useful to protect against undetected loops in a VPLS topology as well as the presence of duplicate MACs in a VPLS service.
If two clients in the VPLS have the same MAC address, the VPLS experiences a high relearn rate for the MAC. When MAC move is enabled, the 7210 SAS-R6 or 7210 SAS-R12 shuts down the SAP or spoke-SDP and creates an alarm event when the threshold is exceeded.
MAC move allows sequential order port blocking. By configuration, some VPLS ports can be configured as ‟non-blockable” which allows simple level of control which ports are being blocked during loop occurrence.