Re: 1 minutes: best downtime story
Date: Fri, 15 Mar 2013 15:00:10 -0600
Message-ID: <51438BDA.2030707_at_gmail.com>
Very early in the days of digital telephone exchanges (switches, technically computers), late 70s, at one of my customer sites:
Switch outage causes air raid siren to sound at 4:30 AM with no hope of turning it off.
This switch was one of the first digital units installed in the region, and one of the first created by this digital switch vendor. During commissioning, the alarms sent to the NOC (network operations center) occurred so frequently that the NOC personnel got into the habit of hitting the 'silence alarm' button.
At 4:30 PM, Sunday, the 'switching to battery' alarm sounds. It is
silenced.
At 5:30 PM, the 'switching to backup generator' alarm sounds. It is
silenced.
At 4:00 AM, the 'generator low on fuel' alarm sounds. It is silenced.
At 4:30 AM, the community's air raid siren sounds. It can not be
silenced because it is on a 'normally closed' relay held open by the
power in the switch room, which has totally failed because the backup
generators are truly out of fuel, and the main breaker tripped, leaving
the telephone exchange without power.
At 7:30 on Monday morning, the mayor of that communty drove to the nearest city to find a pay phone - note, no telephone service either - to call the military to find out why the citizens were being kept awake.
At noon Monday, the NOC operators were re-writing procedure manuals.
-- http://www.freelists.org/webpage/oracle-lReceived on Fri Mar 15 2013 - 22:00:10 CET