Subject: Clarification in VRRP Draft

From: Brian Jewell <[email-masked]>
Date: Fri, 7 Nov 1997 09:30:19 -0800 (PST)

Hi,

Currently I am working on the draft VRRP MIB and wanted to point out an area of 
the VRRP Draft document that I felt needed some clarification.

In Section 3.0, it states: "On an interface running VRRP, each VRRP router must 
be configured with a virtual router identifier for the addresses it owns... . In 
addition, each VRRP router is assigned a priority... ."

In section 6.1.2, entitled "Parameters Per Virtual Router", both the VRID and 
the priority are listed.

I assume that the term "virtual router" is being used in the context of 
"interface", as opposed to, say, a "physical" router. Thus, each interface (on a 
physical router) can have a unique VRID and "priority" assigned (or maybe 
different VRID's and the same priority - but not the same VRID's??).

So to reiterate: a router using VRRP on multiple interfaces *must* have 
different VRID's assigned to each interface, and *may or may not* have different 
priorities assigned (to each interface).

Let me know if I am interpreting this incorrectly. But, either way, I just 
wanted to point out that section 6.1.2 (along with the definition of "virtual 
router" in Section 1.2) could use some clarification such that these parameters 
are not interpreted as being "global", i.e., one per physical router.

Thanks.

Brian Jewell
3Com, Inc.

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From: Mike Shand <[email-masked]>
Date: Mon, 10 Nov 1997 08:55:26 -0000

Brian,
	I agree we could do with some tidying up of terminology. Certainly the term 
'Virtual Router' applies on an interface basis, not just for the entire 
physical router. The reality is that each independent subnetwork (I use the 
term in the OSI sense, not the IP subnet sense; i.e. each set of router 
interfaces {on the same or different physical routers} that have mutual 
connectivity at layer 2), MUST have a non-overlapping set of VRIDs. Interfaces 
which attach to different independent subnetworks MAY have the same VRIDs, but 
if there is any possibility that the relevant subnetworks could become joined 
(for example by an accidental re-plugging, inconsistent bridge filtering 
configurations, etc, etc) then they SHOULD have non-overlapping sets of VRIDs.
	Priority is a matter of flexibility, not correctness, but in general it is 
useful to have independent priorities.

On Friday, November 07, 1997 5:30 PM, Brian Jewell [SMTP:[email-masked]] 
wrote:
> "interface", as opposed to, say, a "physical" router. Thus, each interface 
(on
> a