Maintenance modems and power failures

Sean Donelan SEAN at SDG.DRA.COM
Wed Feb 10 19:54:29 UTC 1999

Hopefully some people will find this related to the operations of their

Ah, maintenance modems.  Why do they always seem not to work just at
the moment you need them.

PG&E released their report on the San Francisco power outage in December.
Most of it was the information previously reported.  One interesting
thing was PG&E lost access to three of their SCADA remote monitoring
units because the modems were plugged into utility power instead of
a UPS.

Most network providers are aware of the secret hiding in most of our
POPs.  Those little sporters and courier modems stuffed into a rack
somewhere plugged into the nearest available outlet, as the only
out-of-band access.  Has anyone come up with a solution for powering
these forgotten pieces of equipment, which doesn't cost more than
the modem itself?

At first you might think it makes sense to power them off the UPS
which is powering the rest of your equipment.  The only problem is
if you are using the maintenance modem to monitor your UPS.  This
is just one of those things which has bugged me for a few years, but
I still haven't come up with a solution I really like.
Sean Donelan, Data Research Associates, Inc, St. Louis, MO
  Affiliation given for identification not representation

More information about the NANOG mailing list