HP NonStop NS manual Common Recovery Operations for Disk Drives page 2

Disk Drives: Monitoring and Recovery Recovery Operations for Disk Drives

Table 10-3. Common Recovery Operations for Disk Drives (page 2 of 2)

Problem Recovery

Unspared defective sectors

To check for unspared defective sectors with SCF:

-> INFO DISK $*, BAD, SEL started, sub magnetic

To check for unspared defective sectors with DSAP at a TACL prompt:

> DSAP $*

•Recovery for DSAP is not needed.

•Recovery for DCOM: use the SCF INFO DISK, BAD command on the affected disk to obtain the bad sector address. Before restarting DCOM, perform the CONTROL DISK, SPARE command.

	For more information, see the Guardian Disk and Tape Utilities Manual.
Nearly full	Recovery Operations for a Nearly Full Database File on page 10-15
database file
Performance	Performance problems can have various causes, including path switches
problems	or a cache size that is too small.
	For information about disk load balancing and increasing cache size, see
	the SCF Reference Manual for the Storage Subsystem.
Corrupt	If both halves of your mirrored system volume become corrupted, use an
$SYSTEM	alternate system disk if one is available. For how to create an alternate
disk	system disk, see the Integrity NonStop NS-Series Planning Guide.
	• For internal SCSI disk drives: if there is no alternate system disk and
	you cannot load from the CONFBASE file, you might be able to
	perform a tape load from a system image tape (SIT) to restore the
	system image files to the $SYSTEM disk (SYSnn and CSSnn
	subvolumes). Then load that image into processor 0 or 1.
	A tape load reinitializes the disk directory. The disk directory is
	overlaid with the directory from the tape. All files on that disk are
	destroyed. Perform a tape load only with the advice of the Global
	Customer Support Center or your service provider.
	• For M8xxx disk drives: you cannot perform a tape load from a SIT.
Failed disk	• Internal SCSI disks: the Support and Service Library on page 1-12
drives	describes replacing disk drives.
	• M8xxx fibre channel disks: these disks are FRUs and can be serviced
	or replaced only by HP-trained service personnel.

HP Integrity NonStop NS-Series Operations Guide—529869-005

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