AGIS Route Flaps Interrupting its Peering?

Mark Kent mark at
Fri Jul 5 07:20:37 UTC 1996

>   So, Mark, you're saying that your routers did not have a problem?
>   If your routers did have a problem, did it affect other providers?

Right.  Our routers did not create any problems that we are aware of.

There was a minor problem at mae-east that appears to have been caused
by the MFS NetEdge.  Several IP addresses in became
unreachable from our router at, but not our router at  We contacted MFS about the problem and they rebooted
the NetEdge in the middle of last night.  Things are back to normal.

Since ANS seems to be passing our interface address as the
next-hop directly to some nets (e.g., Digex and Advantis), the failure
as I described above did lead to a loss of connectivity between AGIS
and at least Digex and Advantis.  Pending the solution of the MFS
problem, it would have been possible to work around the issue if the
affected nets had routed _through_ their transit provider.

>   If it did affect other providers, were you available to resolve
>   the problems in a timely manner?

I do not believe that we affected other providers in the manner
implied by the [internal] Digex report.  We had three bgp sessions
down.  We could not ping those neighbours.  MAE-East transit customers
of other networks could have been affected as I described above, if
they were not protected by "next-hop-self" from their transit

One key point is that we have not received any complaints or reports
of any sort concerning any perceived issues at mae-east from any
mae-east peers.  Digex made no attempt to contact us.  We were already
working with Advantis on the unreachable issue above, but the first we
heard of the "AGIS attacks mae-east" report was when a Digex customer
sent us a report similar to that forwarded to all of you by Cook.

> ]  Gordon Cook asks of an inappropriate audience:
>   I'm not certain it's innapropriate.  If someone's trying to play
>   with us, and causing us problems, then I would like to know about
>   it.

An appropriate audience would have been the AGIS noc and the Digex
noc.  I think the Cook approach was inappropriate because the issue
was purely between Digex and AGIS until Cook distributed it to the
three widespread mailing lists.

> ] The Digex report is seriously flawed.  Ed Kern of Digex has told us
> ] that he is looking into how the conclusions in that report were reached.
>   How is the report flawed?

I see that Ed Kern has already replied indicating that the report was
indeed flawed.  I don't think that there is anything to be gained by
going into further detail.

> ] However, I'm sure that Kern didn't think that he would have to share
> ] his findings with nanog, inet-access, and agislist...
>   Could you share your findings?  If there was a problem, I think
>   we'd all prefer an explanation rather than a finger shaking for
>   having interest.

My key point is that nothing of interest happened.  This was a
non-issue until the misinformation was blasted around the Internet
technical universe.


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