I put this post (below) on www.networking-forum.com and have been researching it this afternoon but not yet found an answer.
Anyone got any ideas.
This has got me stumbled. I have a pretty straight forward lab. 4 Routers as follows.
Router A - ASBR in area 0, redistributing EIGRP routes into the ospf domain (as E2 routes the default).
Routers B and C have uplinks to the ASBR in area 0
Router D has two uplinks to routers B and C but in ospf area 100.
Routers B and C are ABR's.
On router D with out setting the maximum-paths to 1 will equally load balance over the 2 paths (observed with sh ip route), crossing both routers B and C to reach the E2 routes behind the ASBR.
If I hard code maximum-paths to 1 (one route will remain in the ip routing table observed with sh ip route), how does the preferred path get chosen with details below in mind.
- The E2 metric is 20 through out the ospf domain
- The cost to each ABR is 64 from router D
- The cost from each ABR to the ASBR is 64
With these details in mind, everything ties, the cost in each direction for the E2 routes from router D is 148 (obviously I’m missing something). How is the preferred E2 path chosen?