Northern Telecom DMS-100 Series Maintenance Manual page 36

4-2 Disk drive procedures
Procedure 4-1
Disk drive procedures - fault determination
Step Description
1 Enter: (at the terminal)
>DISK MODE (cr)
System response = AO = A ONLY
If disk system status is nonredundant, either
disk in the ONLY mode, go to step 2.
2 Enter: (at the terminal)
>DISK MODE xx (cr)
where: xx = AP = A PRIME
3 Reinitialize the disk - (Procedure 4-5 for
the recommended procedure; Procedure
4-6 for the alternate procedure). This can
take several hours, depending on disk size
and the DISK INIT parameter selection.
Use the short initialization activity followed
by the DISK DEFMAP procedure in most
cases. When the initialization activity (and
DISK DEFMAP procedure) are complete,
go to step 4.
4 Attempt to make the disk mode redundant
- (Procedure 4-4: make disk prime). If
this is unsuccessful, go to step 5 or 6 as
conditions warrant.
297-1001-537 Standard 01.02 December 1993
BO = B ONLY
AP = A PRIME
BP = B PRIME
NONE = No Mode
1
= BP = B PRIME
CAUTION
Subsequent procedures call for the disk commands which may
cause a loss of data if improperly executed. Make sure the
operational disk drive is in DISK ONL Y mode before entering
commands.
2
Notes
Determine the current disk operating mode.
If the disk system mode shows either disk in
the PRIME mode, there is no fault,
procedure complete. Monitor the terminal
for any disk error message repeats.
Attempt to make the disk system redundant.
(if from the AO mode)
(if from the BO mode)
380-Mbyte disk drives w/o 56KB polling;
defaults to "short init" procedure; no "long
init" permitted.
The DISK DEFMAP activity is not allowed
for DPP systems equipped with the 380- or
760-Mbyte disk drives. Return to this point
when complete.
See Table 4-1 for the allowed disk drive
mode changes.
(continued)