SCF Reference Manual for the Storage Subsystem (G06.28+, H06.05+, J06.03+)

Troubleshooting Disks
For more information about troubleshooting disk drives, see the Service and Support Library of the
NonStop Technical Library (NTL).
Starting a Disk
The “START DISK Command” (page 274) makes a stopped disk accessible to user processes. When
finished, the disk is in the STARTED state.
Considerations for START DISK
• New M8xxx disks that have been added and are being used for the first time must be
initialized before they can be started.
• If you are starting a mirrored volume, see “Considerations When Reviving a Mirrored Volume”
(page 98).
• If you receive a DUPLICATE VOLUME message in response to a START command, you must
rename the disk. See “Naming a Disk” (page 88).
• When a system is loaded or when you use the START DISK command, SCF uses the default
volume name. If the default volume name is already in use, the volume is started using the
alternate volume name. If the alternate volume name is also in use, the storage subsystem uses
the volume name in the system configuration database and the disk is left in the DOWN state.
For more information, see “Naming a Disk” (page 88).
• The START DISK command can introduce discrepancies between the disk file labels for SQL
files and the catalog descriptions of the SQL files, thereby making the SQL dictionary
inconsistent. These inconsistencies make the SQL database unusable.
• Use the RESET DISK command followed by the START DISK command to bring up a disk path
that is in any of these states:
◦ STOPPED state, substate HARDDOWN
◦ SERVICING state, substate TEST
◦ SERVICING state, substate SPECIAL
Starting an Unmirrored Disk
1. Check the current status of the disk:
-> STATUS $DISK00
2. If the disk is not in the STOPPED state, substate DOWN, see “Resetting a Disk” (page 103).
3. If the disk is in the STOPPED state, substate DOWN, start the disk:
-> START $DISK00
4. Confirm that the disk has started:
-> STATUS $DISK00
STORAGE - Status DISK \COMM.$DISK00
LDev Primary Backup Mirror MirrorBackup Primary Backup
PID PID
212 *STARTED STARTED *STARTED STARTED 9,262 8,271
5. If the START DISK command fails, see the information on troubleshooting disk drives in the
Service and Support Library of the NonStop Technical Library (NTL).
Starting a Disk 97