MAE West

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1

Another Update from our guys...

Power problems in the MFS facility caused the initial outage. Power has
been restored, but the Gigaswitch has lost it's configuration causing
all
peers to remain down.

Based on some of the mail to this list, it is GIGA 1 at MAE West, 2 and
3 are up. (Most of those complaining are on GIGA 1, Mathew at ACSI is on
GIGA 2 and thinks he's up. I can't reach him directly from NASA/Ames, so
my guess is that he is up, but can only see peers at GIGA 2 and 3 - see
next para...)

By the way, to expand the thread, I have the feeling that the three
OC-3s from NASA Ames side to MFS all go to GIGA 1, which then has fddi
loops to GIGA 2 and then to GIGA 3.

Does anyone know if this is the case?

If it is, seems that a better design would have been to route some of
the OC-3s to the other GIGAs first. If 1 is down, then it can't pass
traffic through to 2 and 3, so there is a single point of failure for
all the switches at MFS.

Rodney Joffe
Chief Technology Officer
Genuity Inc., a Bechtel company
http://www.genuity.net

2

Yes, all 4 OC-3c circuits do terminate at the MFS Gigaswitch-01. It is
a single point of failure, but the ckts must all be on the same switch
in order to use the load-sharing feature.

-Lance-

3

The Gigaswitch constrains us to a loop-free topology, so there's no way to
avoid a single point of failure in a case like this.

The Gigaswitch systems in general have been quite reliable over the last
few years, modulo individual line card failures. The problems we tend to
see are either load-related or caused by human error. This is the first
major outage caused by a Gigaswitch itself that we've seen in a very
long time.

By the way, as of yesterday it's four OC3's between Ames and MFS.
  Steve