VERITAS Storage Foundation 4.1 Oracle Administrator's Guide

Using Storage Checkpoints and Storage Rollback for Backup and Restore Prerelease 8 September 2005, 8:55am
164 VERITAS Storage Foundation for Oracle Administrator’s Guide
on the primary file system, the Storage Checkpoint gradually fills with the original data copied
from the primary file system, and less and less of the block map in the Storage Checkpoint points
back to blocks on the primary file system.
Storage Rollback restores a database, a tablespace, or datafiles on the primary file systems to the
point-in-time image created during a Storage Checkpoint. Storage Rollback is accomplished by
copying the “before” images from the appropriate Storage Checkpoint back to the primary file
system. As with Storage Checkpoints, Storage Rollback restores at the block level, rather than at
the file level. Storage Rollback is executed using the dbed_ckptrollback command or the
GUI.
Note You must run the dbed_update command after upgrading to VERITAS Storage
Foundation 4.0 for Oracle from a previous release. This will allow you to roll back to a
Storage Checkpoint that was created with an earlier version of this product.
Moreover, whenever you change the structure of the database (for example, by adding or
deleting datafiles, converting PFILE to SPFILE, or converting SPFILE to PFILE), you
must run dbed_update.
Mountable Storage Checkpoints can be used for a wide range of application solutions, including
backup, investigations into data integrity, staging upgrades or database modifications, and data
replication solutions.
If you mount a Storage Checkpoint as read-write, the VxDBA utility and GUI will not allow you to
roll back to this Storage Checkpoint. This ensures that any Storage Checkpoint data that has been
modified incorrectly cannot be a source of any database corruption. When a Storage Checkpoint is
mounted as read-write, the dbed_ckptmount command creates a “shadow” Storage Checkpoint
of and mounts this “shadow” Storage Checkpoint as read-write. This allows the database to still be
rolled back to the original Storage Checkpoint.
Note For more information on mountable Storage Checkpoints, see “Mounting Storage
Checkpoints” on page 353 and “VERITAS Storage Foundation for Oracle Command Line
Interface” on page 418.