It seems that bgp is advertising the wrong next hop ip in some instances therefore a recieving router is not populated with all routes.
R1 <---> R2 <---> R3 v1.9.1 - v1.9.1 - v1.8.5
10.60.23.x - 10.60.30.x - 10.60.24.x
NOTE: R1 and R3 are not linked directly, and only via bgp with R2.
NOTE: worked fine previously when R1, R2 had 1.7.0
On R3 I see this.
Dec 19 04:28:17 ubnt BGP[810]: BGP-6: 10.60.30.17-Outgoing [RIB] Update: Prefix 10.60.23.0/24 denied due to non-connected next-hop;
Note: I enabled "debug bgp" to see that in /var/log/messages on R3
On R2 it shows it is sending this to R3
$ show ip bgp neighbors 10.60.30.19 advertised-routes *> 10.60.23.0/24 10.60.23.17 0 65023 i *> 10.60.23.16/29 10.60.30.17 32768 ? *> 10.60.25.0/24 10.60.30.17 0 65025 i *> 10.60.25.8/29 10.60.30.17 0 65025 65001 ?
I believe the next hop should be 10.60.30.17 not 10.60.23.17 as the recieving router has no knowledge of how to get to that network.
Using "show interfaces" on the sending router the two IP's are on the same interface. perhaps bgp picking up the wrong ip?
eth4 10.60.30.1/28 u/u eth4
10.60.30.49/29
10.60.30.17/29
10.60.30.81/30
10.60.23.19/29
Doesn't appear to be an issue with v1.9.1 to v1.9.1 ... perhaps its bluntly just filling it with the received neighbour ip?