HP P6000 Continuous Access Software - Manual (Page 262)

Instant restore from snapshots
This feature allows you to restore data on a virtual disk with data from one of its snapshots. For
example, restore the virtual disk named sales_db with the data from one of its snapshots
sales_db_backup_B.
sales_db_backup_C
|
sales_db_backup_B <====== sales_db
| disk being restored
sales_db_backup_B
replicas to restore from (snapshots)
See also, Instant restore overview (virtual disks) .
Scenario, restoring from "planned points-in-time"
1. At the points-in-time you want (for example, daily), create snapshots or preallocated snapshots
of the disk.
The snapshots contain point-in-time data. Procedures: Creating snapshots and Creating
preallocated snapshots .
2. When necessary, restore the disk from an appropriate snapshot. Procedure .
Instant restore
The instant restore feature in the replication manager uses snapclone replication to copy the contents
of a virtual disk to a like-sized container. The container is then converted to a virtual disk. See
Instantly restoring disks .
Low-level refresh of virtual disks
Update replication manager database entries by manually performing a discovery and refresh of
individual virtual disks.
The action does the following:
•
Performs a discovery refresh at the storage system level to gather the properties of the specified
virtual disks.
•
Updates the replication manager database with the new properties.
Low-level refresh by specifying a DR group
When applied to a DR group, the properties of the log disk and the DR group state are updated.
To update the properties the DR group pair, apply to the source and destination DR groups.
LUN
In each storage system, logical unit numbers (LUNs) are assigned to its virtual disks. When a virtual
disk is presented to hosts, the storage system and the hosts perform I/O by referencing the LUN.
At a low level, a host OS typically reports each storage device that it detects in the format of c#
t# d#, where:
identifies a host I/O controller C #
identifies the target storage system on the controller T #
identifies the virtual disk (LUN) on the storage system D #
262 Virtual disks