SQL/MX 2.x Installation and Management Guide (G06.24+, H06.03+)

Performing Recovery Operations
HP NonStop SQL/MX Installation and Management Guide—523723-004
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INITIALIZE DISK
2. Check that dependent objects residing on other volumes have also been recovered
and re-create objects as necessary.
3. Verify the database by using the mxtool VERIFY utility. For command syntax and
operating guidelines, see the SQL/MX Reference Manual.
4. Make new TMF online dumps of SQL/MX objects that reside on the volume. If the
entire object was re-created, take dumps of the entire object even if one or more
partitions reside on different volumes.
INITIALIZE DISK
The INITIALIZE DISK command prepares the disk for use on the system. This
command deletes any existing files on the volume, deletes the log of spared sectors,
initializes the customer engineer sector and the spare-tracks table, and optionally
labels the disk. To recover an initialized disk volume, follow the steps in ALTER DISK,
LABEL on page 12-37.
START DISK and STOP DISK
Use the STOP DISK command on a mirrored volume pair to make one half of the pair
inactive. The active disk drive of the mirrored pair continues to maintain the current
database, without the protection of mirroring.
After the disk drive is stopped, you can bring the disk up as a phantom drive (without a
name), label the disk with another volume name, or reuse the disk in any other way.
This operation is often done on nodes where nonmirrored disk space is needed for a
short time.
Later, you can return the previously stopped disk drive to its original mirrored state by
performing a START DISK.
You should not use the stopped drive to store production SQL/MX database files. You
typically use the drive for a test database or for temporary space for sort files. You
must ensure that you can make the volume inactive and revive the drive back to its
original mirrored configuration with no effect on the original database.
Use the STOP DISK command on a volume to put a particular volume out of operation.
You can later use the START DISK command to put the same disk back into operation.
Inconsistency is unlikely if the disk brought up is identical to the disk brought down.
Always perform a STOPOPENS DISK on the volume and a CONTROL DISK,
REFRESH on the volume to ensure valid file labels before you make the volume
inactive.
The only exception to the preceding rule is if the entire database has been consistently
brought down as a unit. For example, suppose that you use STOP DISK to bring down
all the backup volumes of the mirrored pairs containing SQL/MX objects in a consistent
Caution. You cannot use STOP DISK on a volume and replace the volume with an earlier
version of that same volume without causing inconsistencies in the database.