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
About Veritas Database FlashSnap
Chapter 5
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NOTE Snapplan creation and validation is only supported on CVM master node.
• dbed_vmclonedb (used on the primary or secondary host)
Mounts and starts a clone database using snapshot volumes. It can also shut down a
clone database and deport its volumes, as well as restart a clone database that has
been shut down. The snapshot image can be brought up on the same host running
the primary database or on a secondary host.
NOTE dbed_vmclonedb does not support instant snapshot for database cloning.
All of these commands can be executed by the Oracle database administrator and do not
require superuser (root) privileges.
NOTE Database FlashSnap operations can be executed from the command-line.
Using Database FlashSnap Options
Database FlashSnap offers three options for creating database snapshots. The option
you choose is specified in the snapplan.
• online
With this option, the tablespaces are put into online backup mode before the
snapshot is created. This type of snapshot is also a valid database backup. Select this
option if you are performing a point-in-time recovery from logical errors.
• instant
With this option, the database can be up and running, and the tablespaces do not
need to be put into online backup mode before the snapshot is created. However, all
the file systems used by the database (including those containing the online redo logs
and control files) are temporarily frozen and the cache is flushed before the snapshot
is created. By freezing the file systems, the snapshot will be a consistent
point-in-time image of the database from which a database clone can be created.
An instant snapshot can be used to guard against data corruption or for off-host
decision-support queries. However, it is not a valid database backup and cannot be
used to perform a point-in-time recovery or off-host backup since tablespaces are not
put into online backup mode before the snapshot is created. The instant option is
much faster than the online option.
• offline
The offline option can be used to clone or back up a database. With this option, the
database must be shut down when the snapshot is created and online redo logs are
required. This type of snapshot is a valid database backup.
In this release of HP Serviceguard for Oracle RAC, Database FlashSnap supports third
mirror break-off snapshots only. Third mirror break-off snapshots are fully
synchronized, full-sized snapshots.