The MPLS WG Archive

[Kireeti Kompella <kireeti@juniper.net>]

Hi Nic,

On Mon, 27 Oct 2003, Nic Neate wrote:

> The issue with that is not with overlap in the problems they are solving,
> but in recovering FRR backup and protected LSPs (which may not be being
> refreshed from upstream) after a restart.  Is this a problem that interests
> you?

Thanks for clarifying.  I agree that networks will have both GR and
FRR.  In principle, I agree that this (recovering FRR sessions during
GR) is a problem that needs to be solved.  However, the premise here
is that during GR (hopefully a small time window, say a couple of
minutes), you have a second failure (of a link or a node).

Yes, it's possible to have multiple failures, but the combination of a
control plane failure recoverable by GR and a link/node failure that
requires FRR seems remote.

A practical solution (that may not satisfy all) is for GR to recover
'regular' LSPs sessions, and to re-initiate FRR sessions; and to abort
GR if a second failure occurs that would have necessitated FRR.

On the other hand, let me not discourage you.  Let's take a look at
solutions, and see how simple/complex they are before ruling on the
protocol work.

Kireeti.
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