About backups and restores of Microsoft Data Deduplication file systems
Microsoft Data Deduplication file systems store files in one of two different states, as follows:
|
Unoptimized files |
Files that do not qualify for optimization (that is, data deduplication within the file system). |
|
Optimized files |
Files that have been deconstructed, and only their unique data segments are stored on the file system. |
NetBackup can do either optimized backups or unoptimized backups of the Microsoft Data Deduplication file systems, as follows:
Table: Microsoft Data Deduplication file systems backup types
| Type | Description |
|---|---|
|
Unoptimized backup |
An unoptimized backup is one in which the policy attribute is not selected. NetBackup re-assembles the optimized files and backs them up as full, intact files. The storage savings of the Data Duplication file system are not retained in the backup. The optimized files remain optimized on the Data Deduplication file systems. The unoptimized files are backed up as full, intact files. NetBackup supports any type of storage destination for unoptimized backups of Microsoft Data Deduplication file systems. |
|
Optimized backups |
An optimized backup is one in which the policy attribute is selected. Only full backups are optimized. For incremental and user backups, each file to be backed up is reconstructed and backed up in its full form. For optimized files, NetBackup backs up the chunk store and the metadata that maps the files to their segments in the chunk store. The chunk store is a location in the file system that contains the data segments that comprise the files. For unoptimized files, NetBackup backs them up as full, intact files. The following are the attributes for an optimized backup of Microsoft Data Deduplication file systems:
The following actions are recommended for backups of Microsoft Data Deduplication file systems:
Optimized backups are supported on the Microsoft operating systems that support Data Deduplication file systems. For supported Microsoft operating systems, see the Microsoft documentation. |
To restore optimized backups, use the option in the Backup, Archive, and Restore interface.
Note the following items regarding restores from optimized backups:
Can only be restored to Microsoft Data Deduplication file systems.
Restores from optimized backups of Microsoft Data Deduplication files systems using the Microsoft deduplication API are slow. First, the image must be mounted through NFS. Then, the image must be accessed through the Microsoft deduplication API, which requests data in the amounts that may be inefficient. The process to restore an entire drive may take a very long time.
Therefore, NetBackup restores all files as full, intact files (that is, non-optimized). The files are then optimized during the next scheduled file system optimization job, or you can initiate optimization manually. You should ensure that you have adequate storage for the restored files in their unoptimized state.