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Veritas NetBackup Snapshot Client Administrator's Guide

Last Published: 2018-02-16

Product(s): NetBackup (8.1.1)

Platform: Linux,UNIX,Windows

Directives for multiple data streams

For multiple data streams, certain directives must be added to the policy's Backup Selections tab.

The number of backups that are started depends on the directives in the Backup Selections tab.
The maximum number of concurrent backups depends on the number of available drives in the storage units and the maximum jobs parameters. An example of a maximum jobs parameter is Limit jobs per policy.

Note:

Only one data stream is created for each physical device on the client. You cannot include the same partition more than once in the Backup Selections list.

The directives that you can use in the Backup Selections list for a FlashBackup policy are as follows:

NEW_STREAM
CACHE=value (the CACHE directive is required)
See Requirements for the cache partition.
UNSET
UNSET_ALL

Each backup begins as a single stream of data. The start of the Backup Selections list up to the first NEW_STREAM directive (if any) is the first stream. Each NEW_STREAM entry causes NetBackup to create an additional stream or backup.

Note that all file paths that are listed between NEW_STREAM directives are in the same stream.

Table: Example of Backup Selections list shows a Backup Selections list that generates four backups:

Table: Example of Backup Selections list

Example	On Solaris systems:	On HP systems:
1	CACHE=/dev/rdsk/c1t3d0s3 /dev/rdsk/c1t0d0s6	CACHE=/dev/cache_group/rvol1c /dev/vol_grp/rvol1
2	NEW_STREAM /dev/rdsk/c1t1d0s1	NEW_STREAM UNSET CACHE CACHE=/dev/cache_group/rvol2c /dev/vol_grp/rvol2
3	NEW_STREAM UNSET CACHE CACHE=/dev/rdsk/c1t3d0s4 /dev/rdsk/c1t2d0s5 /dev/rdsk/c1t5d0s0	NEW_STREAM UNSET CACHE CACHE=/dev/cache_group/rvol3c /dev/vol_grp/rvol3 /dev/vol_grp/rvol3a
4	NEW_STREAM UNSET CACHE CACHE=/dev/rdsk/c0t2d0s3 /dev/rdsk/c1t6d0s1	NEW_STREAM UNSET CACHE CACHE=/dev/cache_group/rvol4c /dev/vol_grp/rvol4

The backup streams are issued as follows. The following items correspond in order to the numbered items inTable: Example of Backup Selections list:

The first stream is generated automatically and a backup is started for /dev/rdsk/c1t0d0s6 (Solaris) or /dev/vol_grp/rvol1 (HP). The CACHE= entry sets the cache partition to /dev/rdsk/c1t3d0s3 (Solaris) or /dev/cache_group/rvol1c (HP).
The first NEW_STREAM directive (2) starts a second stream to back up /dev/rdsk/c1t1d0s1 (Solaris) or /dev/vol_grp/rvol2 (HP). On Solaris systems, this backup uses the same cache partition. On HP systems, a different cache partition must be defined for each stream (CACHE=/dev/cache_group/rvol2c).
The second NEW_STREAM directive (3) starts a backup for /dev/rdsk/c1t2d0s5 and /dev/rdsk/c1t5d0s0 (Solaris) or /dev/vol_grp/rvol3 and /dev/vol_grp/rvol3a (HP). These two partitions are backed up serially within the stream. In addition, the UNSET CACHE directive unsets the previous cache setting and the CACHE= directive sets a new cache partition for this backup.
The last NEW_STREAM directive (4) starts a backup for /dev/rdsk/c1t6d0s1 (Solaris) or /dev/vol_grp/rvol4 (HP). Like the third stream, this one also unsets the cache directive and defines a new cache partition.

Policy-specific directives such as CACHE are passed to the client with the current stream and all subsequent streams, until the directive is redefined or unset.

If the directive is encountered again, its value is redefined.

An UNSET or UNSET_ALL directive unsets a directive that was previously defined in the Backup Selections list. Note the following:

UNSET unsets a policy-specific directive so it is not passed with additional streams. The directive that was unset can be defined again later in the Backup Selections list to be included in the current or a later stream.
UNSET_ALL has the same effect as UNSET but affects all policy-specific directives that have been defined up to this point in the Backup Selections list. If you use it, UNSET_ALL must appear immediately after the second or later NEW_STREAM directive.

More Information

About the cache partition

Requirements for the cache partition

Configuring FlashBackup policy for backward compatibility (UNIX only)