Legato NetWorker ClientPak and Storage Node Installation Guide

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Chapter 3: Configuration
3
How the Inventory Process Works
When NetWorker labels the contents of an autochanger, it registers the location of the
volumes in the autochanger slots when it assigns the volume label. As long as you do
not change the volumes in the autochanger after labeling them, NetWorker can access
the volumes because each volume label is assigned to a specific slot.
However, if you change the contents of the autochanger without performing the
labeling process, or if you move volumes into new slots, you must inform NetWorker
that the autochanger now holds a different set of labeled volumes or that the volumes
are in a different order. This is called taking inventory.
When you inventory the volumes in the autochanger, NetWorker reads the label of
each volume and records its slot number. For example, if you have more than one job
pack for an autochanger, and you do not label the volumes in the new job pack, you
must take inventory each time you remove one job pack and load another one into the
autochanger.
NetWorker provides the capability of reading barcode labels to speed up the inventory
process. We strongly recommend that you use barcode labels if you have a large
number of volumes or change your autochanger contents often. Refer to “How
NetWorker Uses Barcode Labels with Autochangers” in the Legato NetWorker
Administrator’s Guide, UNIX Version, for more information.
Inventory Volumes in an Autochanger
To inventory volumes in an autochanger when you have moved or added volumes,
you can either start the inventory operation in the NetWorker Administrator program
or at the command line as follows:
: NSRJB;info=”-Iv”
After completing an inventory, NetWorker registers the contents of the autochanger
and then proceeds with its network-wide backup and recover services.
Determining Which Volumes Are Used for Backup
The Available Slots attribute enables you to control which volumes NetWorker uses for
backing up data. NetWorker uses all of the volumes in the autochanger for recoveries.
However, you can control which volumes NetWorker automatically selects for
backups by designating a range of available slots in the autochanger.
For example, you might designate slots 1 through 5 for your NetWorker backups in an
autochanger that contains 10 slots. The entries can be a range of slot numbers or a
single slot number.
With two-sided media, the number of available slots is always half the number of labels
(or sides of the optical disks). For example, if you have 32 optical disks, labeled
atlas.001.a to atlas.032.b, you have 64 labels (and 64 sides). However, the number of
available slots is 32.
Important: Make sure you place volumes in all the available slots of the autochanger
so NetWorker can proceed uninterrupted with an automatic backup.