Backup & Recovery

The Technical Services team for Backup and Recovery have produced a number of documents we call "Blueprints".

These Blueprints are designed to show backup and recovery challenges around specific technologies or functions and how NetBackup solves these challenges.

Each Blueprint consists of:

  • Pain Points: What challenges customers face
  • Whiteboard: Shows how NetBackup solves the customer challenges
  • Recommended Configuration: Shows recommended installation
  • Do’s: Gives detailed configurations suggested by Symantec
  • Don'ts: What configurations & pitfalls customers should avoid
  • Advantages: Summarizes the NetBackup advantages

The growth in the use of disk storage (particularly deduplicating disk storage) for backup has highlighted a limitation of disk storage when it comes to site disaster recovery. Tapes can easily be sent to offsite storage and then to a disaster recovery site in the event of a site outage.

Disk doesn‟t offer this flexibility and, while many disk technologies do have the ability to replicate their contents to a compatible array at a remote location accessing the backups with NetBackup is not always a simple matter. The use of Storage Lifecycle Policies and optimized duplication allows disk based backups to be replicated between devices under NetBackup control but, until now, has been limited to the NetBackup domain in which they originated. Thus to achieve a site disaster recovery capability with optimized duplication requires a NetBackup domain that spans at least two geographically remote sites. (This may range from two rooms in the same building/complex to two data centers in separate cities – obviously the greater the separation between the sites the greater the type and severity of disaster you can protect against.)

Some OpenStorage technologies support “out of band‟ replication where the contents of the storage is replicated between devices without NetBackup‟s knowledge. The problem with this approach is that the way in which NetBackup accesses the disk based backups means there is no guarantee the replicated data can be accessed without first recreating the NetBackup catalog importing the entire content of the disk storage using the bpimport command.

The nbcatsync utility goes some way to addressing this problem but relies on being able to restore the catalog from a catalog backup and then “post-process‟ it to reconcile the disk device mappings. While faster than importing the contents of the storage this is still a time consuming process.

Auto Image Replication is a NetBackup feature that protects against site outages by replicating backups between NetBackup domains and cataloging the replicated images in the target domains. It was introduced in NetBackup 7.1 and can be used with many types of disk storage including media server deduplication (MSDP) and some 3rd party OpenStorage devices.

Auto Image Replication also supports simple one-to-one, many-to-one and one-to-many replication configurations. Replication is based on disk storage servers with each source disk storage server being configured with access credentials for one or more target disk storage servers

Where one-to-many replication is used the default behaviour is to replicate images to all of the target storage servers associated with a source storage server. Whether an image is imported into a particular target domain will depend on whether an import Storage Lifecycle Policy exists in that domain. The primary purpose of Auto Image Replication is to create off-site copies of mission critical backups to protect against site loss, it is not intended to extend the storage capacity of a backup domain by allowing backups to be stored in a separate domain. 

You can download the full Blueprint from the link below.