Basic Vls Device Configuration - HP 12000 Design Manual

If deduplication and replication will be configured on the VLS, review
Preparation" (page 132)

Basic VLS Device Configuration

The following steps highlight the considerations for designing the required virtual
libraries/drives/cartridges and standard device configuration.
Identify the number of required virtual libraries. This could be based on the number of separate
SAN fabrics or separate backup application instances/types. See
Libraries" (page
Select a storage pooling strategy for the VLS9X00 and VLS12X00. Identify which pools are
used for which virtual libraries. This could be based on separating cartridges across virtual
libraries, or decreasing the impact of array failure. See
For each virtual library, decide if a high availability design is needed. Always use dual path
for a virtual library changer if the backup application supports this (dual path tape drives are
not recommended unless they are presented to OpenVMS media servers). High availability
design will also affect the virtual drive assignment strategy when the system is in LUN masking
mode, for example by ensuring each media server can access multiple nodes across multiple
paths. See
Select the virtual library/drive types. The HP ESL-E library type is generally preferred due to
its higher emulation limits, but the HP VLS library type (with the same emulation limits as ESL-E)
is recommended for Netbackup because this is officially certified.
Select whether to use shared drives or LUN masked drives. This is based on the number of
media servers that will be using each virtual library and on O/S limitations (such as HPUX
versions prior to 1 1.31 not supporting more than eight library/tape LUNs per target port).
See "Backup SAN Design Guidelines" (page
Select how many virtual tape drives are needed per library. See
Libraries/drives/cartridge Configuration" (page
◦ If you use LUN masking, determine how many virtual drives need to be assigned to each
media server based on the approximate number of concurrent backups needed for each
media server, and develop a strategy for assigning virtual drives to each media server.
◦ If you use shared drives, determine the number of drives based on the total number of
concurrent backup streams required. (HPUX versions prior to 1 1.31 cannot see more
than eight library/tape LUNs per target port.)
Determine the cartridge sizing. See
Configuration" (page
◦ Generally, HP recommends the default 100 GB cartridge size.
If you plan to enable deduplication on this device, assess the average amount of backup
◦
data per virtual tape drive and decide if the default 100 GB cartridge size should be
decreased or increased. See
Determine if each virtual library is used as a replication source library; if so, decide if cartridges
need to be created first in this source library or in the target library. See
Preparation" (page
Gather virtual cartridge barcode template requirements per library.
Assess the required number of slots in each virtual library. Methods of calculation:
◦ Use the total logical amount of tape capacity per library needed to store the retention
policy divided by compression divided by the virtual cartridge sizes.
◦ Check the current total physical tape usage. If you are not changing the backup retention
scheme when moving to VLS, the amount of virtual tape will be approximately the same
130 VLS Configuration and Backup Application Guidelines
and "Replication Preparation" (page 133)
26).
"Multiplexing, Multistreaming, and Multipathing" (page
56).
133).
"Storage Pooling" (page
37).
56).
"Virtual Libraries/drives/cartridge
"Deduplication Preparation" (page
"Deduplication
for more information.
"Single Library vs. Multiple
59).
29).
"Virtual
132).
"Replication