Pool Capacity Calculations; Creating A Backup Of Data; Universal Volume Manager And External Volumes Used As Pool-Vols - Hitachi VSP G1000 User Manual

2.

Pool capacity calculations

You can calculate the required pool capacity by estimating the capacity of
snapshot data to be copied.
Use the following formula:
Capacity of snapshot data to be copied =
Capacity of data written to the same area in the P-VOL during
the period from when snapshot data is stored to when the
snapshot data is deleted
Although the pool capacity is decided according to the estimation, if the pool
capacity exceeds the threshold, address the issue.
If multiple snapshot data are stored, the data may be shared in a pool. In
this case, you can release Thin Image pairs, but the snapshot data cannot be
deleted from the pool. If you release all Thin Image pairs that have snapshot
data containing the shared data, the snapshot data are also deleted from the
pool.

Creating a backup of data

You can create a backup of data using Thin Image. When creating a backup
from the S-VOL after storing snapshot data, the target for the backup is only
the areas where the snapshot data is stored. Therefore, you can create a
backup copy even if the pool capacity is small.
During creation of a backup copy, a significant amount of data is read from
the secondary volume. This may increase the accesses to the primary volume
and degrade the host I/O performance.
Procedure
1.
2.
Related tasks
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Universal Volume Manager and external volumes used as pool-VOLs

You can use Universal Volume Manager (UVM) to connect a VSP family
storage system to other storage systems.
In UVM, a VSP family storage system is referred to as a local storage system,
and the other storage systems are referred to as external storage systems.
With UVM installed, you can use external and internal volumes as pool-VOLs.
Volumes in local storage systems are referred to as internal volumes, and
volumes in external storage systems are referred to as external volumes.
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Hitachi Thin Image User Guide for Hitachi Virtual Storage Platform G Series and F Series
Assign the pool capacity based on the estimate.
Store the snapshot data, or clone pairs.
Use an S-VOL.
Splitting Thin Image pairs to store snapshot data
Thin Image system and planning requirements
on page 136