Subject: RE: [VRRP] And subsecond timers for IPv4

From: Radia Perlman - Boston Center for Networking <[email-masked]>
Date: Fri, 15 Aug 2003 18:12:54 -0400 (EDT)

From: "Don Provan" <[email-masked]>
>>the fact
>>that only the master system sends VRRP packets makes it really hard
>>to negotiate.

Ah right. But perhaps that very property makes it possible without the
extra bits for "I could support higher".

Because maybe if the master can support faster granularity, it sends
both the v2 VRRP messages with 1 second, and the v4(?) with, say,
a timer of 13/100 seconds. Then all the v4 nodes will quickly jump
in when he dies, but any v2 nodes will clunkily sit around and not
notice for several seconds, but if there are any other v4 nodes, 
they will have in the meantime taken over as master.

So the downside is the extra v2 VRRP message. But other than that
it seems like it would work. If there are any other v4 nodes they
would (regardless of priority) jump in ahead of any v2 nodes (assuming
the VRRPv4 message had a timer much less than a second).

Radia

_______________________________________________
vrrp mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/vrrp

---

From: "Don Provan" <[email-masked]>
Date: Mon, 18 Aug 2003 17:54:48 -0700

> they will have in the meantime taken over as master.

Pretty slick. Running v2 and v4 concurrently on the same network for
the same VR. I'm sure we could make it work, but once we've spelled
out all the details about the relation between the two protocols,
what with preemption, priorities, and those kinds of requirements, I
think we'll have a lot of rules for very little gain. After all, if
someone really thinks it's important to failover in .3 seconds
instead of 3 seconds, I'm not sure why they'd be messing around with
v2-only implementations anywhere in the picture.
-don