NetBackup Auto Image Replication (AIR): Overview.

By | August 20, 2015

NetBackup Auto Image Replication (AIR) was released in version NetBackup 7.1 and has been improved so much. 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).

Auto Image Replication supports the following scenarios:

  • One-to-one model - A single production datacenter can back up to a disaster recovery site.
  • One-to-many model - A single production datacenter can back up to multiple disaster recovery sites.
  • Many-to-one model - Remote offices in multiple domains can back up to a storage device in a single domain.
  • Many-to-many model - remote datacenters in multiple domains can back up multiple disaster recovery sites.

NetBackup Auto Image Replication (AIR): Overview

As shown on above figure, the AIR processes are as follows:

Step 1 (Backup) - Originating master server (Source domain, Master server A); Clients are backed up according to a backup policy that indicates a storage lifecycle policy as the Policy storage selection. The SLP must include at least one Replication operation to similar storage in the target domain.

Step 2 (Replication) - Images are replicated from Source domain to the Target domain.

Step 3 (Device notifies NetBackup) - The storage server in the target domain recognizes that a replication event has occurred. It notifies the NetBackup master server in the target domain.

Step 4 (Import) - NetBackup imports the image immediately, based on an SLP that contains an import operation. NetBackup can import the image quickly because the metadata is replicated as part of the image.

Step 5 (Duplication) - this is an optional step. Images can be dupplicated to the tapes.

Auto Image Replication supports cascaded replications (from the originating domain to multiple domains). Storage lifecycle policies are set up in each domain to anticipate the originating image, import it and then replicate it to the next target master.

Let's assume that we have three NetBackup Domains (D1, D2, D3). An example of cascading replication can be as follow:

NetBackup Auto Image Replication (AIR): Overview 2

NetBackup Auto Image Replication (AIR): Cascade Replication

Process overview is as follow:

  1. The image is created in D1, and then replicated to the target D2.
  2. The image is imported in D2, and then replicated to a target D3.
  3. The image is then imported into Domain 3.

In the cascading model, the originating master server for Domain 2 and Domain 3 is the master server in Domain 1. In the cascading model that is represented in figure above, all copies have the same Target Retention - the Target Retention indicated in Domain 1.

AIR supports cascading replications to target master servers, with various target retentions:

NetBackup Auto Image Replication (AIR): Overview 3

NetBackup Auto Image Replication (AIR): Cascade Replication with various retentions

Auto Image Replication requirements

  • Master and Media servers require NetBackup 7.1 and later
  • The Storage across domains must be compatible, already configured, and working. To find out storage compability, please follow Symantec Hardware Compability List.
  • The Enterprise Disk Option is required; no separate additional license is required

Some notes and limitations of Auto Image Replication

  • For catalog backup images, NetBackup supports Auto Image Replication only between the same release levels of NetBackup.
  • Replication between the source domain and the target domain must be between supported versions of NetBackup. NetBackup releases earlier than 7.1 do not support Auto Image Replication.
  • Auto Image Replication does not support synthetic backups.
  • Although Auto Image Replication is a disaster recovery solution, the administrator cannot directly restore to clients in the primary (or originating) domain from the target master domain.
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.

19 thoughts on “NetBackup Auto Image Replication (AIR): Overview.

  1. Felix

    Hi Settlersoman,

    Thank you so much for your wonderful post. This is exactly what I was looking for, more grease to your elbow.



  2. Cameron Lien

    I want to do something like this within a single domain. I have lots of small remote sites that I want to setup local dedupe backups in and then replicate to a central dedupe server for disaster and long term storage. Is that possible? I'm seeing hints of that but not explicitly what I'm looking for.

    1. Mariusz Post author

      Yes it is possible but not by AIR (AIR requires multiple NBU domains). You can just configure replication between storage in each site by SLP.

  3. Rolando

    Thank you very much! Excellent post and reference to know about AIR in a very clear way.

  4. PL

    Hi Settlersoman,

    Thanks for nice post.
    I was wondering if there any way (nbu exe, command) to come to know, if the master server has AIR imported images, on the target master server?


    1. Mariusz Post author


      as AIR is based on SLP, you should use nbstlutil with (repllist or pendimplist or stlilist) option.

  5. srinivas

    Hi ,
    I watch all your posts, it was very helpful for me.. Can you please share us the information for DR configuration step by step.

  6. Rajesh

    Give an example for restoration as well. Suppose if the primary copy image at site D1 expired then how do we do a restore if the copy is available in site D2.

    1. Mariusz Post author

      AIR is not designed to protecting your data against expiration.

  7. Carlos Serrano

    If I replicate the catalog to the second MS, how can i used that???

    I will able to see all the image from the Frist MS for all the clients or what??

    I need to do something else

    1. Mariusz Post author

      You will not able to see all images from the first Master Server, you will see and use only images that you replicate so in your case, only image of the first Master Server.

      If you replicate all images to the second site, you will able to restore all clients.

  8. Jason

    When setting up AIR can I replicate to an existing storage unit or do I have to create a new storage unit for it to replicate to at the target? Do the source and target storage units have to be of equal size? Also, I would like to test AIR but, I am having a problem trying to set it up. What type of storage unit do I have to use to set this up correctly.

    1. Mariusz Post author

      You do not have to create a new Storage Unit and the source and target does not need to be the same size. MSDP is the best way to play with AIR in the lab. There are some OST supported storage by AIR - all those storage you can find on the Compatibility Guide.
      Setting up AIR is easy. I hope that you followed this post.

  9. Andy

    Hi Mariusz ,

    Our Master server (SERVER_A) need to perform a hardware upgrade to replaced by a new machine.
    Can I AIR to a temp server which named SERVER_B, then AIR back to the new machine with name SERVER_A ?

    The version is Netbackup enterprise 7.7.


  10. Jason

    Is there a link where you explain how to recover from AIR? This explanation is very useful but really would like to know what it takes to do a recovery from a DR site.


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