License Capacity Requirements; Planning Pair Volumes - HP StorageWorks P9000 User Manual

Table 1 System Requirements (continued)
Item
Maximum Number of Pairs
Consistency groups

License capacity requirements

The total capacity of your pair volumes must be less than the maximum volume capacity licensed
to you.
After operations begin, you should be aware of capacity requirements in order to keep volumes'
total size within purchased capacity.
P-VOLs, S-VOLs, and volumes that have been reserved for use as S-VOLs must have licensed
capacity. The total of these volumes capacity must not be more than licensed capacity.
Snapshot P-VOLs and pool volumes require the Business Copy license capacity.
The capacity of a volume used for multiple purposes is counted only once; there is no need
to multiply the capacity by the number of purposes it is used for.
When a Thin Provisioning volume is used as a Business Copy P-VOL or S-VOL including a
reserved volume, the capacity of the Thin Provisioning pool is added to the Business Copy
license capacity. The reason is because Thin Provisioning volumes are not updated in real
time. As a result, some write requests may cause data excess, which is saved in the pool.
When your Business Copy volumes exceed license capacity, you are allowed to use the
volumes for additional 30 days. After that, Business Copy operations can no longer be
performed, except for deleting pairs.

Planning pair volumes

You must create volumes for P-VOLs and S-VOLs prior to creating pairs. Review system requirements
for pair volumes in
Before you create a pair, you can reserve a volume as an S-VOL. This insures that no I/O
occurs in the reserved volume before creating a pair. Reserved volumes may only be used as
S-VOLs.
If you use , you can place a group of pairs in a consistency group. Using the consistency
group, you can perform pair operations on all the pairs in the group at the same time, including
the At-Time Split operation with which you can specify the split time. See the HP StorageWorks
P9000 RAID Manager User Guide for information on setting up consistency groups and
performing pair operations.
Requirement
Maximum number possible per storage system is 16,384 pairs (when one S-VOL per
P-VOL). Actual number is based on amount of additional shared memory. See
number of pairs" (page 12)
Maximum number of pairs decreases if LUSE volumes are used.
You can configure up to 128 consistency groups in a storage system, including Business
Copy consistency groups and Snapshot consistency groups.
Note: Business Copy Z pairs, and Snapshot pairs cannot co-exist in the same consistency
group.
You can define up to 8,192 Business Copy pairs in a consistency group.
Note: LUSE volumes that contain n LDEVs should be counted as n volumes. For further
information on LUSE volumes, see HP StorageWorks P9000 Provisioning for Open
Systems User Guide.
A number (0–7F) is assigned to each consistency group. You can specify a consistency
group number when you create Business Copy pairs, or if you do not specify a number,
the storage system assigns a number automatically.
Table 1 (page 10). Also, the following options can be used:
for further information.
License capacity requirements
"Planning
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