SnapProtect - NetApp - Overview

SnapProtect backup enables you to create a point-in-time snapshot of the data used for backups. An effective way to back up live data is to quiesce it temporarily, take a snapshot, and then resume live operations. SnapProtect backup works in conjunction with storage arrays to provide snapshot functionality for backup.

You can use the SnapProtect backup to perform any level of backups (for example, Full, Incremental, or Differential). When you switch from a snap to a traditional backup or vice-versa, the next job is converted to a full backup. While you perform an SnapProtect backup or any subsequent operations, you can use a proxy server to reduce the load on the production server. The backup copy operation uses the proxy to move the snap to backup media. Proxy server is supported with hardware storage arrays.

The following illustration describes the process involved in SnapProtect backup:

Advantages of Using SnapProtect Backup

The following table lists some of the advantages of using SnapProtect backup over other available backup solutions.

Feature Support Generic Software Solution SnapProtect SnapProtect Backup
Backup to Tape
During incremental or log backups only relevant incremental or log data is moved to media which enables significant reduction in media usage.  
Hardware Independent - No dependency on the hardware array  
Snapshot copy, backup copy, and tape copy creation and management are seamless. Application aware snapshots creation can be scheduled. The snapshots can be cataloged/indexed for restore and movement to media based on policies.  
To reduce load on the production server, a proxy server can be used for operations like movement to media and integrity check.  
Restores can be performed directly from media to the application server.  
Ability to mix and match SnapProtect backup with traditional backups. You can perform full SnapProtect backups combined with incremental log backups that are moved to media.  
All data management operations can be performed from the CommCell Console.  

How Does SnapProtect Backup Work

Backup job is scheduled using the CommCell Console. When the backup job is started:

  • The array is accessed to create a snapshot.
  • The snapshot is mounted on the proxy or source computer for post backup operations.
  • The snapshot is unmounted.

This snapshot is used for backup copy operations. This can also be used for restore/mount operations.

During the Backup Copy operations:

  • The snapshot is mounted to the source or proxy computer.
  • The mounted snapshot is treated like a file system and the required contents are read.
  • The file system backup is performed on the Primary Copy of the storage policy.
  • When the backup copy job is finished, the snapshot is unmounted.

Data Aging:

  • The jobs for the snapshot are pruned based on the retention policy for the snapshot copy.
  • The snapshots that are related to the pruned jobs are deleted from the array periodically.

SnapVault and SnapMirror

SnapVault allows a secondary NetApp file server to store SnapProtect snapshots. Multiple primary NetApp file servers can back up data to this secondary file server. Typically, only the changed blocks are transferred, except for the first time when the complete contents of the source need to be transferred to establish a baseline. After the initial transfer, snapshots of data on the destination volume are taken and can be maintained independently for recovery purposes.

SnapMirror is a replication solution that can be used for disaster recovery purposes, where the complete contents of a volume or qtree is mirrored to a destination volume or qtree.

Terminology

The SnapProtect Backup documentation uses the following terminology:

Storage Device A device used for backup or archival purposes.
Storage Array A high-end disk storage system. The SnapProtect software is designed to work in conjunction with the snapshot ability built into the storage array.
Proxy A computer other than the production server on which you can perform SnapProtect operations. A proxy  is used to decrease the load on the production server.
Snapshot Copy An additional copy of the protected data that is used in SnapProtect operations.