VPLS Features
Selective MAC Flush
When using STP as described above is not appropriate, the "Selective MAC flush" feature can be
used instead.
In this scenario, the 7210 SAS M that detects a port failure will send out a flush-all-from-ME LDP
message to all PEs in the VPLS. The PEs receiving this LDP message will remove all MAC
entries originated by the sender from the indicated VPLS.
A drawback of this approach is that selective MAC flush itself does not signal that a backup path
was found, only that the previous path is no longer available. In addition, the selective MAC Flush
mechanism is effective only if the CE and PE are directly connected (no intermediate hubs or
bridges) as it reacts only to a physical failure of the link. Consequently it is recommended to use
the MAC flush with STP method described above where possible.
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7210 SAS M Services Guide