DMVPN: How does CEF know to create GLEAN adjacency for tunnel

HI,

I was studying DMVPN and came across CEF glean adjacency in phase 2.

spoke2 get the routing update with next hop unchanged from router 1. on
Petr INE article there is sentence "this is the key to trigger CEF next-hop
resolution."

My question is exactly how CEF knows that it's not a normal EIGRP update
and it needs to clear a glean adj not invalid one.

Thanks!

Jeremy

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Received on Fri Sep 28 2012 - 15:29:03 ART