Hello Jakob,
If there are 3 paths: P1, P2 and P3
and 2 RR planes.
Plane1 advertises best, Plan2 advertizes 2nd best.
Ok.
When the bestpath P1 goes away, the client can
flap to the 3rd best path, P3, before coming
back to the 2nd bset path P2.
Nope it will not .. see below on comments to your description.
Here is the initial condition:
P1 is best, P2 2nd best, P3 3rd best.
Plane1 advertises P1, Plane2 advertises P2
Perfect !
Because the advertisements from the RR planes are
not synchronized, the order of events could be:
1. P1 goes down: P2 becomes best, P3 becomes 2nd best.
Ok.
2. Client receives IGP message of P1 down: Client chooses P2.
Ok.
3. Client receives P3 from Plane2: Client chooses P3.
This is only when client would not have P2 at all. IMHO corner case (see
below why)
4. Client receives P2 from Plane1: Client chooses P2.
P2 should not go away from client.
Possible fix: Recommend at least as many RR planes
as possible paths for any destination.
Nope.
There are two simple solution here:
- Presence of an extra session from client to either RR to make sure
that your second best is not removed before overall best is advertised
- Small delay on the RR when advertising 2nd best to clients to make
sure overall best is there first in some implementations just
configuring per session mrai may help here.
Cheers,
R.
_______________________________________________
GROW mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/grow
