HP Data Protector A.06.11 Support for VMware vStorage

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During a vStorage backup, Data Protector first creates a snapshot and then copies data from the
consistent state to Data Protector media. Snapshots created for Data Protector purposes (DP
snapshots) are distinguished from other snapshots by the label _DP_VEPA_SNAP_ and a
description that contains the product name and a timestamp. Therefore, avoid using this label for
snapshots that you create for other purposes.
Figure 6: Snapshot tree
The presence of virtual-machine snapshots degrades a virtual machine’s performance; therefore DP
snapshots are deleted when they are no longer needed. The number of DP snapshots that remain
on the snapshot tree after a backup depends on two factors:
The backup type specified
The Data Protector snapshot handling mode selected (See below)
Since the snapshot handling mode can affect virtual machine performance, it is specified per
virtual machine (It is also possible to specify a common mode setting and override this for
individual virtual machines).
Standard operation
During standard operation the vStorage Image method relies on DP snapshots being retained for
differential or incremental backups. The way in which these snapshots are handled depends on the
snapshot handling mode selected.
Note that keeping virtual machine snapshots negatively affects the ESX(i) Server system
performance. In the Mixed mode, for example, where up to two DP snapshots are retained, the
impact is the greatest.
Snapshot handling
The following snapshot handling modes are available. The mode selected must be suitable for the
type of backup chain anticipated.
Disabled: Supports only full backups. The snapshot made at the beginning of a backup session
is used only to create a consistent state. After the data transfer completes, the snapshot is
removed. For details, see Snapshot mode: disabled.
Single: Supports full, differential, and incremental backups in the following backup chains:
Full, differential, differential, differential,...