NetBackup - File Backup and Restore Optimizations - Part 1

By | February 27, 2016

It's not a seldom situation when backups of file server need some tuning and reconfiguration. NetBackup provides some unique and standard features as well to speed up the file server backup. In this post I will show what kind of features we can use for optimization:

  • Multiple Data Streaming
  • Multiplexing
  • Synthetic backups
  • Deduplication
  • NetBackup Accelerator
  • Auto Image Replication
  • True Image Restore

Multiple Data Streaming and Multiplexing

Multiple Data Steaming and Multiplexing are often mislead. The first allows to divide the backup selections into separate jobs (determined by the directives that you specify in the backup selections list). The second sends concurrent backups from one or several clients to a single storage device (e.g. to use tape drives optimally). Multiple Data Streaming provides two advantages: independent data streams (useful when jobs fails because the other job is unaffected) and increased backup speed. Multiplexing is useful for slow networks and clients.

Synthetic backups

Synthetic full backup feature allows to create full backups based on incrementals. Synthetic backup works as follows:

  1. Performing a full backup, also known as a baseline backup. This is a normal full backup operation. E.g. on Sunday.
  2. Performing incremental backups between full backups.
  3. During the next schedule for a full backup, instead of running a normal full backup, an incremental backup is done.
  4. Then, a synthetic full backup is run to merge all incrementals with the first full backup. The newly created synthetic full backup replaces the baseline full backup and becomes the baseline full backup for subsequent synthetic full backup operations.

NetBackup Accelerator

NetBackup Accelerator is a feature that increases the speed of full backups by using track logs on the client to identify changes that have occurred since the last backup. During an accelerator enabled backup only the changed data are transferred to the deduplication storage. It's similar to synthetic backup, however it's done "online".

NetBackup Accelerator for NDMP for NetApp Filers - Overview

NetBackup Accelerator is easy to configure and currently is supported for the following types of data:

NetBackup Accelerator is also used for Copilot for Oracle. This is a new feature available since NetBackup 7.7.1/2.7.1 on Appliances.

Auto Image Replication

NetBackup Auto Image Replication (AIR) lets you replicate the backups that are generated in one NetBackup domain to storage in one or more target NetBackup domains. To replicate images from one NetBackup domain to another NetBackup domain requires two storage lifecycle policies (SLP). The configuration of Auto Image Replication is easy, however you should remember that AIR is designed for disaster recovery.

True Image Restore (TIR)

True Image Restore (TIR) is a feature to ensure that NetBackup restores only those files that were present in the file system at the time of the last backup. It means that files that were deleted prior to the last backup in the selected backup set, will not be restored. TIR can only be enabled for MS-Windows and Standard policy types (for the NBU-Catalog policy type is enabled by default and is not possible to be disabled).


Nowadays, data deduplication is a standard for backup softwares. It looks for blocks or segements of data that are the same and only backs up one of them, even if it occurs multiple times. I already described how NetBackup deduplication works in overview of NetBackup MSDP. To configure Media Server Deduplication Pool (MSDP) please follow How to configure NetBackup Media Server Deduplication Pool (MSDP)? post.
Author: Mariusz

Architect (~ 15 years experience based on passion...) with strong background as a System Administrator and Engineer. Focused on Data Center Solutions: Virtualization/Cloud Computing and Storage/Backup Systems. Currently living in Poland.