Veritas Storage Foundation 5.0 for Oracle RAC Configuration Guide Extracts for HP Serviceguard Storage Management Suite, Second Edition, May 2008

Using FlashSnap for Backup and Recovery

Preparing Hosts and Storage for Database FlashSnap

Chapter 5

corrupted, you can quickly restore them from the snapshot volumes. Snapshot volumes

can be used for a variety of purposes, including backup and recovery, and creating a clone

database.

You must create snapshot mirrors for all of the volumes used by the database datafiles

before you can create a snapshot of the database. This section describes the procedure

used to create snapshot mirrors of volumes.

You can use the vxsnap CLI command to create a snapshot mirror.

Table 5-1 vxsnap Command for Snapshot Mirror Notes

Prerequisites • You must be logged in as superuser (root).

• The disk group must be version 110 or later.

• For more information on disk group versions, see the vxdg(1M)

online manual page.

• Be sure that a data change object (DCO) and a DCO log volume

are associated with the volume for which you are creating the

snapshot.

• Persistent FastResync must be enabled on the existing database

volumes and disks must be assigned for the snapshot volumes.

• FastResync optimizes mirror resynchronization by tracking

updates to stored data that have been missed by a mirror. When

a snapshot mirror is reattached to its primary volumes, only the

updates that were missed need to be re-applied to resynchronize

it. FastResync increases the efficiency of the volume snapshot

mechanism to better support operations such as backup and

decision support. For detailed information about FastResync, see

the Veritas Volume Manager Administrator’s Guide.

• Snapshot mirrors and their associated DCO logs should be on

different disks than the original mirror plexes, and should be

configured correctly for creating snapshots by the system

administrator.

• When creating a snapshot mirror, create the snapshot on a

separate controller and separate disks from the primary volume.

• Allocate separate volumes for archive logs.

• Do not place any datafiles, including control files, in the

$ORACLE_HOME/dbs directory.