wb8foz@mthvax.cs.miami.edu (David Lesher) (05/26/90)
From comp.risks Fri May 25 21:40:37 1990
Date: Fri, 25 May 1990 14:37:39 PDT
From: "Peter G. Neumann" <neumann@csl.sri.com>
Subject: More on Stamford CT Telephone Switch Outage (RISKS-9.93)
AT&T announced today that they have resolved most of the cause of last
Thursday's 18-hour local-call switch outage. Apparently 10,000
subscribers were being moved from the #1A ESS to the new #5 ESS.
During the cutover there is apparently a two minute atomic-action
interval during which nothing works. Due to a burp, call storage was
lost altogether. They found procesor problems that have STILL not
been diagnosed. They also found a cable that had been incorectly
connected last summer, and that remained undetected until the crash.
When the backup failed as well, diagnostics could not be run except by
old-fashioned oscilloscopic probes. [Source: Brief phone conversation
with Seth Angott of {The Advocate} in Stamford CT. Any inaccuracies are
mine.]