Considerations for using the BACKUP SYSTEM utility and DFSMShsm

If you plan to use the BACKUP SYSTEM utility to take volume-level copies of data and logs, all of the Db2 data sets must reside on volumes that are managed by DFSMSsms. You can take volume-level copies of the data and logs of a data sharing group or a non-data-sharing Db2 subsystem.

Restriction: If you use the BACKUP SYSTEM utility to create system-level backups, do not use DFSMShsm to migrate Db2 table spaces and indexes.

The BACKUP SYSTEM utility uses copy pools. A copy pool is a named set of storage groups that can be backed up and restored as a unit; DFSMShsm processes the storage groups collectively for fast replication. Each Db2 subsystem has up to two copy pools, one for databases and one for logs.

Copy pools are also referred to as source storage groups. Each source storage group contains the name of an associated copy pool backup storage group, which contains eligible volumes for the backups. The storage administrator must define both the source and target storage groups. Use the following Db2 naming convention for a copy pool:

DSN$locn-name$cp-type

The variables that are used in this naming convention are described in the following table.

Table 1. Naming convention variables for a copy pool
Variable	Meaning
`DSN`	The unique Db2 product identifier
`$`	A delimiter. You must use the dollar sign (`$`) character.
`locn-name`	The Db2 location name
`cp-type`	The copy pool type. Use DB for database and LG for log.

The Db2 BACKUP SYSTEM and RESTORE SYSTEM utilities invoke DFSMShsm to back up and restore the copy pools. DFSMShsm interacts with DFSMSsms to determine the volumes that belong to a given copy pool so that the volume-level backup and restore functions can be invoked.

Tip: The BACKUP SYSTEM utility can dump the copy pools to tape automatically if you specify the options that enable that function.