Performing Optimized (Extent-Based) Network Share Backups for CIFS Shares

Optimized backups or extent-based backups integrate extent technology to speed up backup operations. Extent based backups break down a file in to small independent extents,that leads to potentially quicker backups and more resiliency to network disruptions. Extent based backups are helpful if the backup content consists of files that are large in size that may cause the available data streams to remain idle.

The size of an extent depends on the size of the file. A large file is split in to small extents and each extent is backed up independently. For example, if a 1 GB file is split into 4 MB size small extents, then 256 extents will be backed up independently.

Extent based backups are automatically applied for files with size greater than or equal to 1 GB.

Benefits

• Faster backups

  Large files are backed up using multiple streams that increases the speed of backups.

• Efficient Backups

  During network disruption, a backup job resumes exactly from the place the backup job was interrupted.

Before You Begin

• Extents based backup is supported only on client computers that use Indexing Version 2.

• Only Optimized and Recursive scan methods are supported.

• Extents based backup is not supported for encrypted files.

• Restore by jobs feature is not supported for extents based backups.

• Enabling extent-based backups on files that are already backed up will create a new baseline of the content for deduplication.

• If you enable extent-based backups on a subclient where backups have been performed, the deduplication ratio is expected to be poor for the first backup.

• If you plan to enable extent-based backups on a large number of subclients, we recommend that you stagger the number of subclients on which you enable this feature so that the backup infrastructure is not overloaded.

Procedure

To the client computer, create the bEnableFileExtentBackup additional setting to back up large files in extents as shown in the following table.

For more information on creating the additional setting, see Adding or Modifying Additional Settings from the CommCell Console.