Re: [GROW] Comment on draft-iops-grow-bgp-session-culling

[Tore Anderson <[e-mail]>]

* Nick Hilliard <[e-mail]>

> Tore Anderson wrote:
> > In other words: in my opinion, BGP session culling should be
> > considered a BCP even in situations where link state signaling
> > and/or BFD is used. IP-transit providers should perform culling
> > towards their customers ahead of maintenance works. Direct peers,
> > likewise.  
> 
> probably not much need if bfd is used because that would operate
> route-to-router.

Quite the contrary, there is very much a need in this case too. If there
are many active routes that will become invalid, converging on
alternate paths (reprogramming the FIB) can take significantly longer
than actually detecting the outage (even if it's detected only using
BGP timers).

> > IXPs aren't at all special regarding the fundamental need for session
> > culling, only in the method by which it is accomplished (i.e., using
> > layer-2 ACLs).  
> 
> Correct, but for direct peers over PNIs, etc, the operator will usually
> have control over the bgp session.  What we're talking about here is a
> situation where there is an intermediate operator which has no direct
> admin control over bgp sessions.

The draft is most definitively also talking about the situations where
the operator does have admin control over the BGP session (section 2.1).

Tore