North American Network Operators Group

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Re: problem at mae-west tonight?

  • From: epg
  • Date: Thu Jul 18 22:13:50 1996


>Matthew Kaufman writes:
> Here's an edited copy of mail I just sent elsewhere, which I believe
> deserves some thought by other network operators :
> Just to update you on this situation:
>   The problem was caused by a bad NetEdge device on the link from
> Netcom to MAE-West. It caused a partial failure of layer 2 connectivity
> from July 13 08:30 PDT until July 15 16:00 PDT. That's over 2 days.
> The current design and implementation of the route server suffers from
> two fatal flaws which, until they are fixed, will mean that I avoid using
> route servers at all costs:
>   1. The route server does not have access to the true state of layer 2
>      interconnectivity, and thus cannot adjust its announcements to avoid
>      "black holes" in the layer 2 fabric, be they caused by missing ATM
>      PVCs or bad bridging devices. Clearly we need a protocol whereby the
>      route server can gain information from the routers about who they can
>      and cannot see.  (Others here have suggested an approach similar to
>      the new OSPF multipoint model)
>   2. The route server does not have a mechanism whereby a client router can
>      force the route server to NOT advertise information to another client,
>      except by editing the policy information and waiting for it to reload.
>      That time-frame is excessive from a network operations standpoint,
>      because every minute that the route server announces a route into a
>      black hole, customers are without service... service which can be
>      restored simply by tearing down the session with the route server, which
>      of course forces it to stop announcing routes to _every_ client...
>      solving the one problem, and causing others at the same time.
> -matthew kaufman
>  [email protected]
> ps. Given that I'd like to refuse to use the route servers, should I _not_
>  peer with them, but make my RADB policy look right, so that other people
>  can tell what my policy is? or should I peer with them, to help their
>  statistics gathering, but set my policy to "don't advertise anything to
>  anyone" ?

We would encourage you to continue to export routes to the route servers
and to register your policy in the RADB. We will explore potential 
solutions to the issues you raise.


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