[c-nsp] stp on me3600 on efp's with locally connected older switch

Christian Meutes christian at errxtx.net
Fri Feb 8 12:27:04 EST 2013

> There isn't much you can do afaik: STP on ACs (CE-only, and consistent port configurations / prone PVSTP), waiting for MST-AG or even MC LAG, keep away from loop-capable ACs per L2 site.

I'am really missing here s/w support for H-VPLS based setups. Currently I see no way other then running full STP on ME-based PEs to solve problem of blackholing on hubs when customer STP converges. With STP on PE, TCN there triggers LDP MAC withdrawal message to hub[s], hence hub[s] can flood to customer site over all remaining PWs until MACs are learned via new PW. 

One solution would be to ship MSTAG also with ME code, which can catch TCNs, feed LDP for withdrawal, without actually running any STP topologies. 

Even simpler would be to let MST or MSTAG on hubs inside of VFI-based bridge-domain working, plain customer TCN processing would be sufficient here. That way SP network would only be involved in MAC table flushing on TCN reception - real STP only in customer equipment, which cares about topology.

Cisco, any plans here?

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