Snapshot-based incremental backups

You can implement snapshot-based incremental backups to increase the speed at which these backups are performed.

During a snapshot-based incremental backup, OneFS checks the snapshot taken for the previous NDMP backup operation and compares it to a new snapshot. OneFS then backs up all files that was modified since the last snapshot was made.

If the incremental backup does not involve snapshots, OneFS must scan the directory to discover which files were modified. OneFS can perform incremental backups significantly faster if the change rate is low.

You can perform incremental backups without activating a SnapshotIQ license on the cluster. Although SnapshotIQ offers a number of useful features, it does not enhance snapshot capabilities in NDMP backup and recovery.

Set the BACKUP_MODE environment variable to SNAPSHOT to enable snapshot-based incremental backups. If you enable snapshot-based incremental backups, OneFS retains each snapshot taken for NDMP backups until a new backup of the same or lower level is performed. However, if you do not enable snapshot-based incremental backups, OneFS automatically deletes each snapshot generated after the corresponding backup is completed or canceled.

After setting the BACKUP_MODE environment variable, snapshot-based incremental backup works with certain data management applications (DMAs) as listed in the next table.

Table 1. DMA support for snapshot-based incremental backups
DMA
Supported
Symantec NetBackup
No
Note Image

You can enable snapshot-based incremental backups through an environment variable.

Networker
Yes
Avamar
Yes
CommVault Simpana
Yes
Tivoli Storage Manager
No
Symantec Backup Exec
No
NetVault
No
ASG-Time Navigator
No