Bad routes update

Peter Tattam peter@jazz-1.trumpet.com.au
Thu, 22 Jul 1999 15:22:17 +1000 (EST)


On Wed, 21 Jul 1999, Masaki Hirabaru wrote:

> >> ->2) There are a lot of route flapping even within the valid pTLA
> >> ->space.  A long time ago, I tried to figure out the origins, but I
> >> ->gave up to continue it for all the occasions. It keeps happening.
> >> 
> >> If we aggregate, I think we will see this diminish. many routes that flap
> >> come from statics that point to interfaces that go down, etc... If we
> >> aggregate, we won't see the affects of these, except in the case of yoru
> >> IBGP, where you will want your own specifics.
> 
> I don't think that most of the flapping on 6bone comes from
> interface up/down. And, pTLA routes are flapping, so we can not
> diminish them by aggregation.

My guess it's a result of having to use tunnels over Ipv4.  Some of the Ipv4
network is unstable IMHO, and this could be reflected into the 6bone.  I don't
think this is coincidental as I suspect that a significant body of users
deploying IPv6 are doing so because of their own perceived instability of IPv4
services.  We for one experience this - our backbone provider won't give us an
honest answer as to what the problem is, and is indicative of the way things
really are.  For some regions, choice of backbone provider is limited too, so
letting the market decide is not a complete answer.

Peter

> 
> >> ->3) There are a couple of strange routes outside the 6bone pTLA
> >> ->space drafting over the 6bone. We could get it covered by
> >> ->imposing the routing policy rather than solving the real problem.
> >> 
> >> Filter them. That way, they will be gone. If you look closely enough, you
> >> can see 10/8 v4 space around. You just have to filter it at your edges to
> >> make sure it doesn't affect anyone. While I would personally like for these
> >> people to fix the problem, in this case, you can only control your own
> >> routing domain, thus going around them with a filter would be just as
> >> handy, and effectively the same thing.
> 
> Let me explain how they are strange. They have a strange as path
> and are flapping. It would indicate something wrong on 6bone.
> 
> If the routing policy intends to solve the current 6bone routing
> issues, it would not work.  It will just decrease the size of
> routing table but may introduce another complexity that may make
> it harder to catch the real problems.
> 
> Masaki
> 

--
Peter R. Tattam                            peter@trumpet.com
Managing Director,    Trumpet Software International Pty Ltd
Hobart, Australia,  Ph. +61-3-6245-0220,  Fax +61-3-62450210