NonStop Operations Guide for H-Series and J-Series RVUs

M8xxx Fibre Channel Disk Drives
The most common disk problems on an NonStop NS-series system are intm-errors-exceeded and
slow-IOs-threshold-exceeded errors on the Fibre Channel loop.
Such errors are often normal. However, if they cause problems on a Fibre Channel loop, power
the affected disk down and up again. This procedure can solve the problem temporarily.
Unless you are a qualified service provider, you cannot perform any physical actions on disk
drives. However, operators can use OSM and SCF commands.
Recovery Operations for Disk Drives
These SCF commands control DISK objects:
DescriptionCommand
Terminates the operation of a disk drive immediately,
leaving it in the STOPPED state, HARDDOWN substate.
ABORT
Changes attribute values for a storage device.ALTER
Bypasses one or more disks in a Fibre Channel disk-drive
enclosure.
BYPASS
Issues disk-specific commands.CONTROL
For a disk drive, causes the backup processor to become
the primary processor and the primary processor to become
the backup processor.
PRIMARY
Changes the name of a disk drive.RENAME
Puts a disk drive in a state from which it can be restarted.RESET
Initiates the operation of a disk drive.START
Terminates the operation of a disk drive in a normal
manner.
STOP
Switches paths to a disk drive.SWITCH
For more information, see the SCF Reference Manual for the Storage Subsystem.
Table 29 Common Recovery Operations for Disk Drives
RecoveryProblem
Use the Disk Compression Program (DCOM) to consolidate
disk space. See “Disk Compression Program (DCOM)”
(page 222).
Free-space fragmentation
Disk full 1. Use DSAP to identify large, old, and little used files.
2. If you are authorized:
• Use the BACKUP utility to back up these disk files to
tape and then purge them from the disk. Do not purge
important system files.
• Move files to another disk. Do not move important
system files.
• Ask users to purge files.
For more information about these utilities, see “BACKUP”
(page 222) and “Disk Space Analysis Program (DSAP)”
(page 222).
“Recovery Operations for a Down Disk or Down Disk Path”
(page 152).
Down disk or disk path
Recovery Operations for Disk Drives 151