HP Archive Backup System for OpenVMS Guide to Operations

3.1.12 Volume Sets
Saving and Restoring Data
3.2 Catalogs
only one pool per archive. If you do not specify a pool, then only volumes that have no pool
defined can be used for the archive (this is also known as the scratch pool).
The volume sets attribute indicates which volume sets are currently being used by save requests
using the archive. There may up to the maximum saves number of volume sets currently being
used. These volume sets are those to which the next save operation will be written to the archive.
This attribute is normally maintained by ABS and you should not modify it unless there is a
pressing need to remove one or more of the volume sets from the list and let ABS allocate new
volume sets. Under no circumstances should you add volumes to the volume set list.
3.2 Catalogs
3.2.1 Catalog Name
3.2.2 Catalog Node
3.2.3 Type
An ABS catalog contains historical information about ABS save operations. This historical
information includes the location of data that was saved using ABS. For this purpose, ABS provides
a default catalog named ABS_CATALOG.
Some sites can operate efficiently using only ABS_CATALOG provided by ABS. However,
using additional catalogs can improve your ABS operations:
• Speed of record insertion
• Speed of lookup operations
• Segregation of saved data
• Regular catalog file maintenance
This name is used to reference the catalog. There are no required or ad-hoc conventions for catalog
names, so they can reflect their usage in your environment.
Catalogs are node specific. You have to specify the MDMS node name where the catalog
resides. An empty catalog node name means the local node where the command was issued or
where the request executes. In a VMScluster, multiple nodes can share the same catalogs on a
common disk as long as they have direct access to the catalog files. During a save operation ABS
always accesses the catalog on the local node even though a different node name is specified in
the archive. During a restore operation the catalog lookup will be performed for the catalog at
the specified node. This allows to restore data that has been saved on another node.
ABS supports four types of catalogs, which are hopefully self-explanatory:
• DISKS - This catalog type only stores information about save requests performed. No information
about individual filenames are stored in the catalog. The size of a DISKS type catalog
is drastically smaller than the FILES catalog type. Save requests using this catalog type
must be of type FULL and only specify a disk name. Staging does not apply to these catalogs.
Selective restore can be performed from a DISK type of catalog using ABS.
To view information about saved disks use the /SAVE qualifier with the “SHOW CATA-
LOG” command. The show output lists the data saved, the volume ID and save set name
used.
Saving and Restoring Data 3–5