Veritas FlashSnap Point-In-Time Copy Solutions 5.0 AdministratorÆs Guide, HP-UX 11i v3, First Edition, May 2008

58 Database recovery

Creating Storage Checkpoints

To create Storage Checkpoints, select 3 Storage Checkpoint

Administration > Create New Storage Checkpoints in the VxDBA utility.

This can be done with a database either online or offline.

Note: To create a Storage Checkpoint while the database is online, ARCHIVELOG

mode must be enabled in Oracle. During the creation of the Storage Checkpoint,

the tablespaces are placed in backup mode. Because it only takes a few seconds

to take a Storage Checkpoint, the extra redo logs generated while the

tablespaces are in online backup mode are very small. To optimize recovery, it is

recommended that you keep ARCHIVELOG mode enabled.

Caution: Changes to the structure of a database, such as the addition or removal

of datafiles, make Storage Rollback impossible if they are made after a Storage

Checkpoint was taken. A backup copy of the control file for the database is saved

under the /etc/vx/vxdba/ORACLE_SID/checkpoint_dir directory

immediately after a Storage Checkpoint is created. If necessary, you can use this

file to assist with database recovery. If possible, both an ASCII and binary copy

of the control file are made, with the binary version being compressed to

conserve space. Use extreme caution if you attempt to recover your database

using these control files. It is recommended that you remove old Storage

Checkpoints and create new ones whenever you restructure a database.

Rolling back a database

To roll back a database (for example, after a logical error has occurred)

1 Ensure that the database is offline. You can use the VxDBA utility to display

the status of the database and its tablespaces, and to shut down the

database:

■ Select 2 Display Database/VxDBA Information to access the

menus that display status information.

■ Select 1 Database Administration > Shutdown Database

Instance to shut down a database.

2 Select 4 Storage Rollback Administration > Roll Back the

Database to a Storage Checkpoint in the VxDBA utility, and choose the

appropriate Storage Checkpoint. This restores all data files used by the

database, except redo logs and control files, to their state at the time that the

Storage Checkpoint was made.