You can perform the following types of backups, either immediately or on a schedule:
- Full backup: Backs up the entire virtual machine. This backup is the most comprehensive.
- Incremental backup: Backs up virtual machine data that changed after the most recent backup.
- Synthetic Full backup: Consolidates virtual machine data from the most recent full backup with subsequent incremental backups.
- To display the Differential backup option, add the bEnableVSADifferentialBackup additional setting to the CommServe system as shown in the following table.
Changed Region Tracking for Nutanix AHVChanged Region Tracking (CRT) is an optional mechanism that enhances the backup performance of Nutanix AHV virtual disks. When you enable CRT, the system uses REST API to detect the changed meta-data regions of the virtual disks by comparing snapshots. With this comparison, CRT provides better backup performance than traditional cyclic redundancy check (CRC) backups because the API query identifies the changed regions for the incremental backups as well as identifying those regions that are spare (zeroed), which can reduce read operations for full backups.
How It Works
CRT uses REST API to determine the changed meta-data regions in AHV virtual disks by comparing two snapshots (a snapshot of the current virtual disks environment against the snapshot that was obtained during the previous CRT-enabled streaming backup). Only the changed meta-data regions that the API detects are backed up and written to backup media. After the backup completes, the current snapshot will become the previous snapshot for comparison in the next CRT-enabled backup operation. Only one snapshot per VM will be retained for comparison.