Sprint IPv6

Pierfrancesco Caci ik5pvx at gmail.com
Thu Oct 2 10:56:34 CEST 2008

On Thu, Oct 2, 2008 at 10:39 AM, Gert Doering <gert at space.net> wrote:

> As a customer, we really really dislike seeing 6PE used in our upstreams'
> networks because it means that traceroute6 is becoming useless - you can
> see that "there is a problem somewhere in the upstream network", but
> you have no chance of pinpointing things like packet loss or (worse)
> black holes to the routers/links where it's happening.

this happens with  ipv4 as well. Of course you can make intermediate
steps visibile by setting 'mpls ip propagate-ttl', but then you'd end
up with a horde of whiners complaining that traceroutes take 500ms...

> In this specific case, there were some problems with RSVP reservations
> that led to MPLS tunnels going down completely in case of link outages,
> which the control plane didn't notice - so BGP claimed "everything is
> fine" while the data packets disappeared into a big black hole.
> (I'm not sure on the underlying details, as we've never done 6PE+RSVP,
> but that's how things have been explained to me).

Ok. Was the problem confined to IPv6, or did you experience some fun
in v4 as well, at the same time?

 Pierfrancesco Caci, ik5pvx

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