Hewlett Packard Enterprise HPE XP7, User Manual, Page: 13 / 311

Snapshot tree components
Volume type Volumes that can be used Description
Root Logical volume (LDEV)
Volume (L1 pair of the P-VOL) in
the top layer of a snapshot tree.
The logical volume of the P-VOL
contains THP V-VOLs (V-VOL of
which provisioning type is Thin
Provisioning in RWC, or V-VOL
created by
raidcom add ldev
-pool
in RAID Manager).
Node THP V-VOL
Volumes located between the
root volume and leaf volumes.
S-VOL of the root volume (or
another node volume), and the P-
VOL of a leaf volume (or another
node volume).
Leaf THP V-VOL
Volumes in the bottom layer of a
snapshot tree.
S-VOL of the root volume or a
node volume, which is not a P-
VOL of any pair.
Maximum number of Fast Snap pairs
The maximum number of pairs that can be created on the XP7 storage system is 1,048,575.
Consistency and snapshot groups
A consistency group can include Fast Snap (FS), Business Copy (BC), and Business Copy MF (BC MF)
pairs. Use consistency groups to split the Fast Snap pairs that are defined in the group. Splitting the pairs
using the group assures data consistency at the time the XP7 Storage system receives the request.
A snapshot group is a group of only Fast Snap pairs. Use consistency or snapshot groups to perform Fast
Snap tasks on all of the pairs within the group. You define Fast Snap pairs to a snapshot group when you
create the pairs.
The following table shows the differences between consistency groups and snapshot groups.
Item Consistency group Snapshot group
Pair limit per group 8,192 8,192
Limit 2,048 2,048
Data consistency Guaranteed Not guaranteed
Software application from which you can define pairs FS, BC, and BC MF FS
For more information about defining Cnt Ac-S pairs in consistency groups, see the HPE XP7 Continuous
Access Synchronous User Guide .
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