Netbackup General Guidelines; Netbackup Deduplication Guidelines - HP 12000 Design Manual

NetBackup General Guidelines

The following NetBackup guidelines apply to a VLS regardless of whether deduplication is enabled
or disabled:
HP VLS Library Emulation: When configuring the VLS for use with NetBackup, select "HP VLS"
as the library emulation. NetBackup requires the use of this emulation in all HP VLS products
for device support purposes.
Barcode formats: When configuring the barcode formats for the virtual cartridges, do not
exceed eight characters.
Disable multiplexing: Even though multiplexing is supported, HP does not recommend it for
virtual libraries because of the performance impact on restores and deduplication. Because
you can create additional drives easily in the virtual library and allocate them to Media Servers
as necessary, sufficient backup streams can be concurrently written without requiring
multiplexing. Be aware of the Netbackup Device Manager limitation of 128 tape drives per
media server.
Tape block size: Set the tape block size to 256 KB (maximum supported size) using <install
path>/netbackup/db/config/SIZE_DATA_BUFFERS.
Storage unit fragment size: Set the storage unit fragment size to default, 1TB, with the box
unchecked.
Enable multi-streaming: Multi-streaming (a backup job concurrently writing to multiple virtual
tape drives) provides efficient use of bandwidth when data objects reside on different physical
disks/arrays.
Avoid multiple retention periods per cartridge: Avoid mixing different retention periods on the
same cartridges; this is off by default.
Number buffers: Set the number of data buffers to 32 or 64 using <install
path>/netbackup/db/config/NUMBER_DATA_BUFFERS.

NetBackup Deduplication Guidelines

In addition to the NetBackup general guidelines, the following guidelines apply to a VLS with
deduplication enabled:
NetBackup raw/image file backups: NetBackup raw file backups will only deduplicate if the
differencing algorithm for the corresponding policy is set to Backup-level. If the policy for these
files is set to File-level, these files will not be deduplicated.
Volume pools: Use as few as possible to quickly fill up tapes.
Multistreaming Storage Groups in Exchange: You can use multiple streams when creating a
backup policy, but the name of each stream must be unique within each policy. Deduplication
is only performed on backup sets that have the same policy and group (a group is defined
as the longest common path name in the backup set). If you are multistreaming the Storage
Groups in an MS Exchange Information Store, ensure that the databases reside in different
fully-qualified paths
Oracle RMAN Scripting: See
Tape Retention Planning: Create media pools based on retention period. Mixing retention
periods will prevent cartridge expiration reclamation and leads to poor storage utilization.
Space used for the shorter retention backup is not reclaimed until all backups on the tape are
expired. That is, the backup application cannot reuse/reformat the tape until all backups have
exceeded their protection period. The backup application will not reuse expired cartridges
until all spare formatted virtual cartridges are used, so in this case HP recommends either
removing unneeded virtual cartridges or creating a script on the cell server to automatically
reformat expired cartridges on a regular basis.
140 VLS Configuration and Backup Application Guidelines
Oracle RMAN Scripting for details.