HP 3000 Manuals HP 3000 Manuals
Restoring from Multiple Devices (RESTORESET)
To RESTORE files from multiple devices, use the RESTORESET parameter in
the RESTORE command to reference the multiple devices. Use of the
RESTORESET parameter is explained in the following pages.
Sequential Devices
You can use sequential device configuration when you have a large set of
files to RESTORE from a number of tapes and you want to speed up the
process. The sequential device configuration is described under "Using
Tape Devices Sequentially," in Chapter 3, "Preparing Storage Devices."
To RESTORE files from sequential devices:
1. Mount the tapes on all of the devices you plan to use.
2. Use the FILE command to give each device a filename that indicates
its position.
3. Use the RESTORESET parameter in a RESTORE command to reference the
multiple devices.
For example, to RESTORE files from three sequential devices, use the
following set of commands:
:FILE SEQ1;DEV=7
:FILE SEQ2;DEV=8
:FILE SEQ3;DEV=9
:RESTORE ;@.@.@;RESTORESET=(*SEQ1,*SEQ2,*SEQ3)
NOTE Do not back reference the filename of a tape device immediately
before the name(s) of the file(s) you are restoring when using the
RESTORESET parameter. Instead use a placeholder for the missing
parameter normally supplied when using a single tape device. The
placeholder is provided by the use of the first semicolon (;) in
the RESTORE command.
The above RESTORE command restores all system and user files from three
sequential devices. The parentheses surrounding back-referenced
filenames group the devices into a device pool.
When RESTORE has transferred all the files from the first tape on the
first tape device, it immediately begins restoring files from the second
tape on the second tape device. While RESTORE continues, you can unload
the first tape and mount a new tape on the drive. When RESTORE finishes
restoring the files on the last device, it reverts to restoring files
from the first device. The process continues to cycle through the
devices in the device pool until it has restored all the files you
specified.
If you gave the tape devices a single filename such as:
:FILE T;DEV=TAPE
Enter the following RESTORE command to RESTORE files from a set of three
sequential tape devices:
:RESTORE ;@.@.@;RESTORESET=(*T,*T,*T)
You can RESTORE files that were created using parallel devices or
parallel device pools in a sequential configuration. For example, to
RESTORE a set of reels that have been created using parallel device
pools, you must use the following logical order to mount the reels on
sequential devices: A1, A2....B1, B2 and so on. (The first alphabetic
character, in capital letters, indicates an original, unique parallel
set; the second numeric character indicates an original sequential reel
within the set.) That is, mount A1 first, followed by A2. The reel that
you mount prior to B1 should be the last "A" reel.
NOTE Sequential RESTORE is not available for labeled tapes.
Parallel Devices
A parallel device or parallel device pool configuration can be used for
restoring files. Therefore, you can use the same designations with the
RESTORESET parameter that you can use with the STORESET parameter. Refer
to Chapter 3, "Preparing Storage Devices," for information on storing to
multiple devices.
If you gave the tape devices a single filename such as:
:FILE T;DEV=TAPE
Enter the following RESTORE command to copy files from a set of two
parallel tape devices:
:RESTORE;@.@.@;RESTORESET=(*T),(*T)
Describe parallel devices in the RESTORESET parameter by enclosing each
back-referenced device filename within parentheses. Use commas to
separate devices.
To RESTORE files from parallel device pools, use parentheses to group the
devices into pools. Separate the devices in the pool from one another
with commas. Commas also separate each device pool.
For example, the following commands copy files from two parallel device
pools. Each device pool contains two sequential devices. In the
following example, RESTORE uses a total of four devices divided into two
device pools.
:FILE PPA1;DEV=7
:FILE PPA2;DEV=8
:FILE PPB1;DEV=9
:FILE PPB2;DEV=11
:RESTORE ;@.OPERATOR.SYS;RESTORESET=(*PPA1,*PPA2),(*PPB1,*PPB2)
If you gave the tape devices a single filename such as:
:FILE T;DEV=TAPE
Enter the following RESTORE command to copy files from a set of parallel
device pools:
:RESTORE ;@.@.@;RESTORESET=(*T,*T),(*T,*T)
Notes Parallel RESTOREs can be performed only with tape sets that were
created with a parallel STORE parameter. A sequential RESTORE can
be used with any tape set.
Parallel RESTORE allocates every subset of the tape set (for
example, STORESET=(*T1),(*T2) creates two subsets) to distinct
parallel devices or device pools, and expects a volume belonging
to the subset to be mounted on its allocated device or device pool
only.