FW: Concert Network Maintance - 8.5 Upgrade Domain 4 (UK)

Regan, Sharon Sharon_Regan at newcourt.com
Tue Jan 26 18:39:15 UTC 1999

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From: BrownLJ at stentor.ca [mailto:BrownLJ at stentor.ca] 
Sent: Tuesday, January 26, 1999 1:36 PM
To: Regan, Sharon
Cc: GreenKB at stentor.ca; GodardD at stentor.ca; WongR at stentor.ca;
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Subject: Concert Network Maintance - 8.5 Upgrade Domain 4 (UK)

Ms. Regan;

On February 12th, 1999, Concert will be upgrading Subnet 4  (UK) to System
Software 8.5. This upgrade is to begin at 23:00 GMT (18:00 Eastern)
with a maintenance window duration of 10 hours.

The initial impact to the Frame Relay network will be minimal; the expected
downtime will be less than 45 seconds for most nodes and
up to 2 minutes of data interruption for some. There is also a possibility
of reroutes, although the chance is small and would be
like any other reroute that would occur upon a trunk failure.

There is an expectation that approximately 10% of the PVC's will experience
failures for which a script will be executed, on each node,
to correct the problem. All issues that have been observed with the Subnet
5 (Germany) upgrade have been addressed in this script
and it is expected to take approximately 2 hours to complete. The lower the
number of PVC's on a node, the quicker the reroute time.

The reroutes will be noticeably faster as System Software 8.5 supports
trunk based loading.  Please note however, by resetting
connections throughout the Subnet, each PVC will be impacted twice.  This
is unfortunate but unavoidable in order to
accomplish the upgrade.


Linda J. Brown
CCSC - Concert Canada Service Center
Concert Change Management

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