Hi Laz,
Thanks for the reply, it makes sense.
I have uploaded the PCAP. And this is how I have interpreted it:
14 R10 sends an Update to R8 with the Init flag set. Unicast
16 R8 sends an Update to R10 with the Init flag set and an acknowledgment of R10’s update (No. 14). Unicast
17 R10 sends an Update containing all its routes. Multicast.
18 R10 sends an Ack to R8’s update Init. Unicast
19 R8 sends an Update containing routes. Multicast.
20 R10 sends an Ack to R8 for its updates. Unicast
21 R10 re-sends an Update containing all its routes (I guess because it hasn’t received an Ack yet). Unicast
22 R8 sends an Ack to R10
Aside from multicast being used instead of unicast for the synchronization, the following exchange is what I really don’t understand:
23 R10 sends an Update containing R8’s networks out of the interface connected to R8. Multicast
24 R8 sends and Ack back. Unicast
25 R8 sends an Update containing R10’s networks out of the interface connected to R10. Multicast
26 R10 sends an Ack back. Unicast
Why has the exchange in numbers 23-26 happened? Split horizon is not disabled on R8 or R10’s interface, but they are sending the routes back out of the interfaces they learned them from.
Btw, I’m using CML for this. Not sure if that makes a difference.
11f6a5f8-c12b-40ca-92a5-8166bc443dc7.pcap (4.5 KB)
Thanks,
Sam