Incremental backup and restore support for Kubernetes
NetBackup Kubernetes release 10.4 provides backup support using differential, cumulative and automatic schedules.
Incremental backups reduce the backup window significantly in NetBackup. In this method, NetBackup, backs up only the data that has been changed since the subsequent full backup.
Incremental backup supports only the filesystem type persistent volumes. The block type persistent volumes backups are always full backup irrespective of the schedule types.
Note:
Snapshot copy is always a full backup due to storage class limitation. Apart from snapshot copy, backup from snapshot, duplicate copies have incremental support.
Restore from a complete recovery point performs point in time restore. All the data till that recovery point is restored.
Restore from a recovery point marked as Complete = No (incomplete) cannot be possible.
Image chain validation operation is performed for recovery point copies, the validation is reflected in the Complete field of recovery point of each backup copy.
Complete field is set to Yes when all the related images of the recovery points are present.
Note:
Recovery point completeness marked as No (Complete = No) if incremental backups chain is incomplete or any image is missing from the image group.
AIR is supported only for the full schedule backup jobs. AIR function is not supported for Differential Incremental, Cumulative Incremental, or Automatic schedules.
Manually imported incremental images can be restored from a valid recovery point (Complete = Yes).
After manual import, if the recovery point is marked as Incomplete, then the image chain might be broken due to few images missed out during the manual import operation.
To recreate an image chain for manual import operation
- Check
/usr/openv/netbackup/logs/bpdbm/root{dateformat}.logand find log lineprevious backup relationship. To restore the relationship, know which image/ images are missed out from the manual import operation. - Import the missed out images and run the following command to create a new image chain.
`bpimage -update -id <backupid> -previous_backupid <previous backup id>`
USE_CTIME_FOR_INCREMENTALS option for NetBackup clients:
The USE_CTIME_FOR_INCREMENTALS entry changes how NetBackup determines whether or not a file has changed. This entry causes the client software to use both modification time and inode change time during incremental backups to determine if a file has changed (mtime and ctime).
DO_NOT_RESET_FILE_ACCESS_TIME option for NetBackup clients:
The DO_NOT_RESET_FILE_ACCESS_TIME entry specifies that if a file is backed up, its access time (atime) displays the time of the backup. By default, NetBackup preserves the access time. NetBackup resets the previous value of the backup.
To set the datamover properties: User must set or update the flag in NetBackup primary server specific configmap created under NetBackupKOps namespace on Kubernetes cluster.
Example:
apiVersion: v1 data: datamover.properties: | image=reg.domain.com/datamover/image:latest VERBOSE=5 VXMS_VERBOSE=5 USE_CTIME_FOR_INCREMENTALS=YES DO_NOT_RESET_FILE_ACCESS_TIME=YES version: "1" kind: ConfigMap metadata: name: backupserver.sample.domain.com namespace: <NetBackupKOps-Namespace>
Following the schedules are supported in NetBackup Kubernetes workload.
Automatic
Full
Differential Incremental
Cumulative Incremental
A protection plan with different schedules can be configured as follows
To backup with different schedules types
- In a protection plan, select backup type (Full, Differential Incremental, Cumulative Incremental, Automatic).
- Under configure schedule for snapshot, provide values for recurrence and snapshot retention.
Provide values for Backup from snapshot retention period.
- In the start window tab, set a schedule time and then click Add.
- Under Schedules and retention section, click Add schedule to add multiple schedules in the same protection plan (Differential Incremental, Cumulative Incremental).
- Select a storage and follow the remaining steps to run a backup job.
In the case of automatic type schedule, based on recurrence of snapshot schedule get resolved after creation of protection plan.
If recurrence is less than one week, then a single differential and full schedule is created.
Follow the recommendation for Retention values in a protection plan for incremental schedules.
To perform a restore from recovery point for any copies (snapshot, backup from snapshot, duplicate), it is recommended to keep the retention duration of the copy for longer period.
Example, to restore from a backup copy, retention of Backup from Snapshot must be more than Snapshot copy. Otherwise, the backup copy will expire and recovery point will be marked as COMPLETE = NO
In such cases, the warnings appears on the NetBackup web UI as follows:
It is recommended to set backup retention period more than snapshot retention period.
It is recommended to set duplication retention period more than the backup retention period.
Always add full backup schedule along with cumulative backup schedule. Otherwise, every Cumulative backup will be Full backup.
By default, the Backup from Snapshot option is always enabled for incremental backup types.