EIGRP External routes AD


Hi. Excuse if this question has been asked. In the topology I have BB1 performing mutual redistribution. Once the OSPF routes are redistributed into OSPF, the distributed route will show in the EIGRP domain with an AD of 170. After playing around with BB1, I changed the distance of the external EIGRP router to 100 which is less than OSPF. After changing that, the routes were still showing as eigrp learned. As far as I understand, a router will install a route in its routing table depending on the more trusted IGP. In this case I have changed it to 100 which is lower than OSPF and the routes are still showing as OSPF. Is there an internal mechanism that does not allow the router to install the router as an EIGRP route or is it because the route is incomplete because the next-hop ip(interface)is not known to EIGRP. Thanks in advance for your assistance, much appreciated.

Hello John

You must keep in mind that the routing table of the router actually doing the redistribution isn’t affected by the redistribution itself. So that means that any routes it learns about from OSFP will always appear in the routing table as being learned from OSPF regardless of what changes you may make to the AD of EIGRP.

Take a look at this lesson, and pay particular attention to the Verification section 1.2.2.

I hope this has been helpful!


All clear now, thank you Laz.

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