EIGRP equivalent to OL-bit and Router LSA Max Metric?

fredrikjjfredrikjj Member Posts: 879
OSPF and IS-IS both have features that prevent a router from becoming a BGP transit router as it rejoins a topology. If you need more details, read this quote:
Imagine an internal BGP topology where the BGP next hop for remote destinations is some IP address at the edge of the AS. To reach this next hop, the routers do a recursive lookup in their forwarding tables. Now, if we introduce a new router with a lower IGP cost to the BGP next hop, this could become the preferred transit router to reach the the external networks. The IGPs typically converge faster than BGP, and because of this, it’s possible that traffic for the external destinations will be black holed on the new router; it simply doesn’t have the BGP prefixes in its FIB yet.

To solve this problem, both IS-IS and OSPF have features that allow a router to signal to the rest of the topology that it shouldn’t be used for transit yet. In IS-IS the Overload Bit is set in the router’s LSPs. This OL bit disqualifies the router from being a transit router in the shortest path tree. Once it’s determined that BGP is converged as well, the OL bit is removed. This is done by explicitly configuring set-overload-bit on-startup wait-for-bgp.

OSPF accomplishes the same thing with the max-metric router-lsa on-startup wait-for-bgp feature. It sets all metrics in a router’s type 1 and type 2 LSAs to their maximum value. This ensure that the router won’t be used for transit. Once BGP is ready, the LSAs are reflooded with their normal metric values. Both of these features will eventually timeout after 10 minutes if BGP fails to converge.
(I wrote that so feel free to point out anything that's wrong)

My question is, does EIGRP have a similar feature? I'm curious because the BGP book that I'm reading uses EIGRP in all of its examples, but doesn't mention anything about this.


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