[j-nsp] vpls loop avoidance

[Sebastian Wiesinger]

* Phil Bedard <philxor at gmail.com> [2011-10-13 02:01]:
> Coming soon to at least one platform, but haven't heard anything about
> Juniper.  The active/standby mechanisms work pretty well but active/active
> using something like SPBM or TRILL would be nicer.

One problem with active/standby is mac aging on the CE switch(es).
When the primary PE goes down, the backup PE takes over and the
CE-switches learn mac addresses on the link towards the backup PE.
Now when the primary link comes online again, the VPLS on the primary
PE goes active, forcing the standby PE to deactivate VPLS. The CE
switches still have the mac addresses learned on the port to the
standby PE so you have to wait until the mac addresses age out (or a
packet with that source mac comes in from the primary PE).

Regards,

Sebastian

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