Weird Behavior with EIGRP Stub Routers

Hello @ReneMolenaar,

I ran into a peculiar issue after watching Keith Bogart’s CCNP ROUTE course on INE.

I was zooming through “EIGRP Convergence :: Part 3” where he talks about Stub routers, and explains that, just like Cisco white pages, directly connected and summary routes should be the only routes advertised from Stub routers.

Keith said that, that response is what you should answer with on your exam. However, he made a caveat regarding real life. He proves otherwise on his physical equipment, and so did I on my C7200 router in GNS3.

The short and long of it is that I have three routers enabled; R1, R2 and R3. I have RIP enabled on R1, and R2, whereas EIGRP on R2, and R3. I redistributed RIP into the EIGRP process, and ran the redistribute connected command.

The expected behavior is that “only” directly connected, and summary routes will be advertised by a stub router. However, after running Wireshark I noticed that the “Redistributed” stub option was set even though redistribute connected routes should not be advertised unless the eigrp stub redistributed connected command is specified.

I have an online friend who has proven this with VIRL images in EVE-NG, I’ve proven this with GNS3, and Keith has too on physical equipment. I’m not sure if this is a bug, or if someone in the community at Cisco can answer this. But, it’s odd that nigh every resources available says one thing, yet Wireshark proves otherwise.



Heloo Austin,
I have seen this too, when we set stub option the 4th bit from right in stub options is always going to be set to 1. No matter what you do, if you set “eigrp stub receive-only” this redistiributed bit is still going to be 1 in EIGRP hello and on top of it, Receive-Only bit stays on 0.

I think that Wireshark is using wrong alias text for this bit, its more likely telling us that we are using stub option and nothing more.