About true image restore
A True Image Restore (TIR) recovers the contents of a directory as they were at the time of the previous incremental or full backup. The files deleted before the backup are not restored.
The option, in D-NAS policy, specifies whether the NAS policy can collect the information necessary to perform a true image restore.
NetBackup begins gathering TIR data for each incremental or full backup of the policy. The TIR information is collected for each volume regardless of whether any files were changed.
Collect true image restore is not supported along with Vendor Change Tracking (VCT) unless you have enabled accelerator. If the NetBackup admin wants to enable both TIR and VCT options in the backup policy, then accelerator must be enabled in the NAS policy.
NetBackup admin can perform TIR restore using single-stream or multi-stream restore.
The table below shows the files that were backed up in the /vol1/dir/ directory between 12/01/2024 and 12/04/2024. The NAS policy that ran the backups had the option selected.
Table: Sample backups taken before a TIR
Day | Type of backup | Backed-up files |
|---|---|---|
12/01/2024 | Full |
|
12/02/2024 | Incremental |
|
12/02/2024 | Incremental |
|
12/03/2024 | Incremental |
|
12/04/2024 | Incremental |
|
Note:
The dashes ( ------ ) indicate the files were deleted before the backup.
If you restore the 12/04/2024 version of the /vol1/dir/ directory, you can see the following results:
After a regular restore
The restored directory contains all files and directories that ever existed in /vol1/dir/ from 12/01/2024 (last full backup) through 12/04/2024:
file1 file2 dirA/fileA dirB/fileB file3 dirC/fileC file4
After a TIR
The restored directory contains only the files and directories that existed at the time of the incremental backup done on 12/04/2024:
file1 file2 file4
NetBackup does not restore any of the files that were deleted before the 12/04/2024 incremental backup. NetBackup did not restore these files or directories because they did not exist at the time of the incremental backup. The last selected incremental backup was the reference for the TIR.