Polling Disks From A Non-Redundant Mode - Northern Telecom DMS-100 Series Maintenance Manual

4-130 Disk drive procedures

Polling disks from a non-redundant mode

The DPP normally stores AMA data simultaneously on both disks .
However, if the DPP can't be polled, the disks fill up with AMA data.
When both disks reach 95% full, the disk system goes to the nonredundant
(ONLY) mode. The off-line disk is filled with AMA data that must be
preserved and polled; the second disk writes over its data and continues to
collect AMA data from the DMS-100. This procedure provides for polling
the AMA data from both disks when the disk mode is ONLY (A or B) or
non-redundant.
It is expected that the inability to poll the DPP disks has been corrected
before this procedure is attempted. When this procedure is complete, the
DPP system is in the normal, redundant, PRIME mode.
To shorten this procedure, coordinate this activity with the Collector site at a
time of minimum call record (AMA) traffic from the DMS-100.
Use Procedure 4-61 to poll the primary AMA data from both disks while in
nonredundant mode caused by disks filling up with AMA data.
Procedure 4-61
Polling disks from a nonredundant mode
Step Description
1 Enter: (at the terminal)
>VALPARM LOGHDR ON (cr)
then
>SITDAT WRITE (cr)
2 Enter: (at the terminal)
>DISK MODE (cr)
System response =
DISK MODE AO
(or)
DISK MODE BO
297-1001-537 Standard 01.02 December 1993
Note: This procedure must not be performed at DMS-100 to DPP block
input rates that exceed four blocks per second.
Note: It is recommended that this be done during lowest traffic!
Notes
Turn on the display of block headers as they
are written to disk. This provides a visual
indication of current AMA traffic.
Save to disk.
Determine the current disk mode. In order
to poll the AMA data, a manual disk mode
change back to the original disk must be
performed. The original disk has the oldest
AMA data. At this time, the disk mode is set
for the second disk, which is collecting new
primary AMA data.