Veritas Storage Foundation™ for Oracle 5.0.1 Administrator's Guide

primary file system, and less and less of the block map in the Storage Checkpoint
points back to blocks on the primary file system.
You can set a quota to limit how much space a file system will give to all storage
checkpoints, to prevent the checkpoints from consuming all free space. See the
command dbed_ckptquota for more information.
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 make sure the storage checkpoint is not mounted when the
dbed_ckptrollback command is issued.
Note: You must run the dbed_update command after upgrading to Veritas Storage
Foundation Product version: 5.0.1 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 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. The dbed_ckptumount command
unmounts a Storage Checkpoint.
Space requirements for Storage Checkpoints
To support Block-level Incremental (BLI) Backup and storage rollback, the file
systems need extra disk space to store the Storage Checkpoints. The extra space
151Using Storage Checkpoints and Storage Rollback
Space requirements for Storage Checkpoints