Veritas NetBackup™ Administrator's Guide, Volume I

Note the following about the NetBackup Accelerator:

• NetBackup Accelerator requires the Data Protection Optimization Option license. For the latest information on licensing, contact your Veritas sales or partner representative.

• Supports the disk storage units only. Supported storage includes Media Server Deduplication Pool, NetBackup appliance, cloud storage, and qualified third-party OST storage.

  See the NetBackup Hardware Compatibility List for supported storage types.

• Storage unit groups are supported only if the storage unit selection in the group is Failover.

• Supports the MS-Windows and Standard policy types. Supports all features of NetBackup that work with the MS-Windows or Standard policy types.

  Note:

  Accelerator operates differently when used for backup of virtual machines, NDMP, or Oracle databases. For full details, see the following:

  NetBackup for VMware Administrator's Guide

  NetBackup for NDMP Administrator's Guide

  NetBackup for Oracle Administrator's Guide

  The guides are available from the following location:

  http://www.veritas.com/docs/DOC5332

• Accelerator backups ignore the policy attribute that resets the atime on files after backup.

  By default, NetBackup records the file access time (atime) for each UNIX file that it backs up, and then resets the atime after the file is backed up. Resetting the atime in this way causes the change time (ctime) to update as well. The Reset file access time to the value before backup policy attribute normally controls this behavior (the default is enabled).

  When NetBackup Accelerator is used to perform backups, NetBackup does not reset the atime after the file is backed up, regardless of the policy attribute setting. NetBackup does not reset the atime (which avoids updating the ctime) because a ctime update would require a loss in Accelerator optimization.

  See Client Settings properties for UNIX clients.

• Supports the full backups and incremental backups.

  See Accelerator backups and the NetBackup catalog.

• Supports all platforms, file systems, and logical volumes that NetBackup supports.

• Supports the Windows NTFS and ReFS change journal (Use Change Journal) but does not support the VxFS change journal.

• For every policy that enables the Use Accelerator option, Veritas recommends at a minimum the following backup schedules:

  A full backup schedule with the Accelerator forced rescan option enabled.

  Another full backup schedule without the Accelerator forced rescan option enabled.

  See Accelerator forced rescan option (schedule attribute).

• If Collect true image restore information is enabled in the policy, NetBackup performs a regular file system scan to determine the files and folders to include in the backup. It also queries the change journal to help determine which files have changed.

  More information is available on the Use change journal option and the Accelerator:

  See Accelerator and the Windows change journal.

• If a previous backup of the client does not exist, NetBackup performs a full backup and creates a track log on the client. This initial backup occurs at the speed of a normal (not accelerated) full backup. Subsequent Accelerator backups of the client use the track log for accelerated backup speed.

  Note:

  When you first enable a policy to use Accelerator, the next backup (whether full or incremental) is in effect a full backup: It backs up all files in the Backup Selections tab. If that backup was scheduled as an incremental, it may not complete within the backup window. For example, when you upgrade policies to 7.7 and first enable the Use Accelerator option, note: Make sure that the next backup window is large enough for a full backup.

• NetBackup retains track logs for future Accelerator backups. Whenever you change the policy's backup selections list, NetBackup does a full non-accelerated backup of the selections that were changed or added in the list. The unchanged backup selections are processed as normal Accelerator backups.

• If the storage unit that is associated with the policy cannot be validated when you create the policy, note: The storage unit is validated later when the backup job begins. If Accelerator does not support the storage unit, the backup fails. In the bpbrm log, a message appears that is similar to one of the following:

  Storage server %s, type %s, doesn't support image include.
  

  Storage server type %s, doesn't support accelerator backup.

• Accelerator requires that the storage have the OptimizedImage attribute enabled.

• Veritas recommends that you not enable Expire after copy retention for any storage units that are used with storage lifecycle policies (SLP) in combination with Accelerator. The Expire after copy retention can cause images to expire while the backup runs. To synthesize a new full backup, the SLP backup needs the previous backup image. If the previous image expires during the backup, the backup fails.