Hi,
Please see the link below. I was putting a lab together for testing, and basically R2 receives the external eigrp route for 34.34.34.0/24, but R1 doesn't. The problem was the originating router-id (from R3) was the same as R1, so R1 ignores the route.
http://gyazo.com/73a0b278949f6cdf9460be2dcf180826
The log message you get from R1 is below
DUAL-6-EVENT: IP-EIGRP(0), 21 Ignored route, dup router: 192.168.1.1 DUAL-6-EVENT: IP-EIGRP(0), 22 Ignored route, neighbor info: 12.12.12.2 FastEthernet0/1 DUAL-6-EVENT: IP-EIGRP(0), 23 Ignored route, metric: 34.34.34.0 256007680
So my question is, how do you troubleshoot this problem methodically (if eigrp event-logs are disabled)? My initial approach would be to check for distribute lists or ACLs between R2 and R1 that block the 34.34.34.0/24 subnet from being advertised. After that, I would be stuck (until I did this test lab). I can't think how you would methodically approach this to identify its a router-id problem. As I created this lab, i knew the problem existed, so on R2 i just did a #sh ip eigrp top 34.34.34.0 255.255.255.0 and saw the originating router-id was the same. But is that the approach you take? just check acl's and distribute lists between R2 and R1, then check for the originating router-id?