Snapshot Trees And Cascaded Pairs; Creating Cascaded Pairs - Hitachi VSP G1000 User Manual

When cloning pairs, use a logical volume as the P-VOL and a DP-VOL as the
S-VOL.
If you split pairs that have the clone attribute, the data of the entire P-VOL is
copied to the S-VOL asynchronously to create a clone of the primary volume.
When the copy completes, pairs are deleted and the S-VOL is unpaired
(becomes a DP-VOL). This volume can be used as a volume in the same
status as the P-VOL. This operation is referred to as cloning pairs.
A maximum of 1,024 clones (including the number of snapshots if you store
them) can be created by using Thin Image.
Cloning pairs includes operations after the P-VOL is copied to the S-VOL, until
volumes are unpaired. Volumes created by cloning are not included.

Snapshot trees and cascaded pairs

Snapshot trees are Thin Image pair configurations where snapshot data is
stored.
The volume in the top layer of the snapshot tree is the root volume. Volumes
in the bottom layer are leaf volumes.

Creating cascaded pairs

Thin Image S-VOLs can be paired with secondary layer S-VOLs. First layer
(L1) S-VOLs can also be paired with secondary layer (L2) S-VOLs. A
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Hitachi Thin Image User Guide for Hitachi Virtual Storage Platform G Series and F Series
Overview of Thin Image