AT&T MERLIN LEGEND Release 3.1 System Programming Manual page 365

Memory Card
The system places the automatic backup into one of two designated files:
backup in
the older of the two files and overwrites it. The system performs this file "toggle"
each time it performs an automatic backup.
While the backup is in progress, you cannot access system programming
functions, your Personal Directory, or alarm clock functions (any programmed
alarms are temporarily deactivated).
If any type of programming is taking place at an extension during the automatic
backup procedure, the backup is canceled. The system does not re-attempt the
backup.
If an automatic backup fails for any reason (including a system-busy condition),
all of the programmed alarm buttons on system operator consoles light and the
information is recorded in both the permanent error log and the last 10 error
logs. The system does not re-attempt the backup.
Also see "Backup Messages" for information about errors that may occur during
the automatic backup procedure.
NOTE:
If an automatic backup fails for any reason (except when the failure results from
the memory card being write-protected) the automatic backup feature is turned
off. Follow the procedure below to reprogram automatic backups.
Summary: Automatic Backup
Programmable by
Mode
Idle Condition
Planning Form
Factory Setting
Valid Entries
Inspect
Copy Option
and . If both files are empty, the system places the
If both files already contain backups, the system selects
System manager
All
Not required (No extensions are allowed to be in
programming mode including the system programming
console)
Form 1, System Planning
Weekly backup: Sunday at 2:00 am
(if daily backup is selected, time is factory set for 2:00 am)
Daily: hhmm (00 to 23; 00 to 59)
Weekly: dhhmm (0 to 6; 00 to 23; 00 to 59)
No
No
Common Administrative Procedures
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