About Pool-Vols; Creating Pools - HP XP7 User Manual

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About pool-VOLs

Pool-VOLs are grouped together to create a pool. When a new pool is created, the available
pool-VOLs are selected in the Select Pool VOLs window and added to the Selected Pool Volumes
table. Every pool must have a pool-VOL with System Area.
When adding a volume to the pool for which Smart Pool is enabled, note the following:
Up to three different drives types/RPM are allowed between all the pool-VOLs to be added.
Volumes to be added to the same pool must have the same RAID level across all the same
drive type/RPM pool-VOLs.
For example, you cannot add a volume whose drive type/RPM is SAS/15k and whose RAID
level is 5 (3D+1P) when a volume whose drive type/RPM is also SAS/15k but whose RAID
level is 5 (7D+1P) is already in the pool
Up to three values are allowed for Drive Type/RPM for the volume.
If you increase the pool capacity by adding a pool-VOL, a portion of the existing data in the pool
automatically migrates from an older pool-VOL to the newly added pool-VOL, balancing the usage
levels of all the pool-VOLs. If you do not want to automate balancing of the usage levels of
pool-VOLs, call HP technical support for assistance.
Thin Provisioning does not automatically balance the usage levels among pool-VOLs if the cache
memory is not redundant or if the pool usage reaches up to the threshold.
The pool-VOLs contained in a pool can be added or deleted. Removing a pool-VOL does not delete
the pool or any related THP V-VOLs. You must delete all THP V-VOLs related to the pool before the
pool can be deleted. When the pool is deleted, all data in the pool is also deleted.

Creating pools

The following procedure tells how to create a pool. This procedure is for setting up Thin Provisioning,
but optional steps are shown for setting up Smart Tiers, Smart Tiers Z if you chose to add tiers to
your storage system.
Before creating a pool, you must install the proper amount of shared memory, and you must have
a V-VOL management area in shared memory. When shared memory is added, the V-VOL
management area is automatically created. To add shared memory, contact your HP representative.
One pool-VOL with system area is defined for a pool. The priority of the pool-VOL with system
area is assigned according to the data drive type. The available capacity of the pool-VOL with
system area is deducted from the management area capacity. The management area capacity
stores the management information of program products that use the pool. If Thin Provisioning,
Smart Tiers, or Fast Snap is used on an open system, 4.2 GB are used as the management area
in the pool-VOL with system area.
When the pool is created, a pool-VOL with system area is assigned the priority shown in the
following table.
Priority
1
2
3
4
5
122 Configuring thin provisioning
Data drive type
SAS7.2K
SAS10K
SAS15K
SSD
External volume