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A Storage Checkpoint is a persistent image of a file system at a given instance in time. Storage Checkpoints use a copy-on-write technique to reduce I/O overhead by identifying and maintaining only those file system blocks that have changed since a previous Storage Checkpoint was taken. Storage Checkpoints have the following important features:
Storage Checkpoints persist across system reboots and crashes.
A Storage Checkpoint can preserve not only file system metadata and the directory hierarchy of the file system, but also user data as it existed when the Storage Checkpoint was taken.
After creating a Storage Checkpoint of a mounted file system, you can continue to create, remove, and update files on the file system without affecting the image of the Storage Checkpoint.
Unlike file system snapshots, Storage Checkpoints are writable.
To minimize disk space usage, Storage Checkpoints use free space in the file system.
Storage Checkpoints and the Storage Rollback feature of Veritas Storage Foundation for Databases enable rapid recovery of databases from logical errors such as database corruption, missing files and dropped table spaces. You can mount successive Storage Checkpoints of a database to locate the error, and then roll back the database to a Storage Checkpoint before the problem occurred.
Symantec NetBackup for Oracle Advanced BLI Agent uses Storage Checkpoints to enhance the speed of backing up Oracle databases.
See the Symantec NetBackup for Oracle Advanced BLI Agent System Administrator's Guide.