HP B6960-96035 - Manual (Page 276)

allocation of logical volumes on physical disks, but you can influence it with a choice
of protection characteristics.
RAID
Redundant Array of Inexpensive Disks (RAID) technology is used to control the way
in which the data is distributed across the physical disks within a disk array. Various
levels of RAID are available, providing different levels of data redundancy and data
security, speed and access time. For example, RAID0 provides no duplication of
data, RAID1 provides duplication of all data, RAID5 provides protection of data by
parity.
The snapshot integrations for Data Protector are designed to work with disk arrays
that use the snapshot technology, such as HP StorageWorks Virtual Array and HP
StorageWorks Enterprise Virtual Array.
Snapshot concepts
In a typical basic setup using the snapshot technology, a single disk array might be
connected to separate application and backup systems. The disk array can be used
as a storage device by both the application system and the backup system and logical
volumes can be mounted on either. Using this arrangement, the application system
uses logical volumes within the disk array to store its data during its normal operation.
The logical volumes storing the application system data are for the needs of Data
Protector snapshot integrations also referred to as source volumes. When a snapshot
backup is performed, the application data residing on the source volumes is replicated
and written to other logical volumes of the same disk array, also referred to as target
volumes. This replicated data is also referred to as snapshot data and presents an
almost instantaneous point-in-time copy of a given filesystem or volume. The set of
thus created target volumes is referred to as replica. Once the replica for snapshot
data is created, the primary data can continue being modified without affecting the
backup operation.
Snapshot concepts 276