Backup options
The defaults for new backups are set under Settings; open them with Settings at the top right of the start page. Advanced settings on the backup page shows the options of the backup you are setting up.
Backup strategy
| Strategy | What is stored | Files needed for a restore |
|---|---|---|
| Full backup, then create incremental backups | A full backup first; afterwards only the changes since the previous backup. Saves space and time. | The full backup and every incremental backup up to the selected one. |
| Full backup, then create differential backups | A full backup first; afterwards all changes since the last full backup. | The full backup and the selected differential backup. |
| Only create full backups | A complete copy of the selected data every time. Needs the most space. | That full backup alone. |
Review the storage requirement and the efficiency of the chosen strategy from time to time and adjust it if needed.
Execution policy
The Execution policy determines after how many change backups – incremental or differential backups – a new full backup is created. This keeps the chain of change backups short, so a restore stays fast and simple.
Enable the option and specify the number of change backups after which a new full backup is created. Weigh the storage space of full backups against the speed and safety of a restore.
Backup technology
| Technology | Meaning |
|---|---|
| Used sectors | Copies only the sectors of a drive that contain data. Saves space and time; the recommended method. |
| Forensic backup | Copies every sector of the drive, including unused areas with potentially recoverable data. Suitable for legal or investigative purposes. |
| Direct forensic backup | Creates an exact copy directly from the disk, so the original state is not changed. Available only in Fortress Mode. |
Forensic backups need storage space for the full size of the backed-up drive. The direct forensic backup can only be performed in Fortress Mode; enable it under Tools before starting such a backup. See Fortress Mode and startup medium.
Compression method
Enable compression to reduce the size of the backup files. Without compression, the data is stored in its original size, which can be faster but needs more space.
| Method | Meaning |
|---|---|
| Lempel-Ziv algorithm (default) | Balanced compression without a noticeable effect on the backup speed. |
| Lempel-Ziv algorithm (maximum) | Stronger compression that takes more time and reduces the file size further. |
| ZIP deflate compression | A common, widely supported compression method. |
| BZIP method (1K block size) | Efficient compression with a small block size; faster, but compresses less. |
| BZIP method (4K block size) | A balance between compression rate and speed. |
| BZIP method (9K block size) | The highest compression rate of the BZIP options, at the expense of speed. |
Stronger compression lengthens the backup and uses more system resources.
Backup format
| Format | Meaning |
|---|---|
| O&O DiskImage format | The recommended standard format. It allows all backup options and the restore with O&O DiskImage. |
| Virtual Hard Disk Format (VHD) | The Microsoft format for virtual hard disks, used by virtualization solutions. |
| Virtual Hard Disk Extended Format (VHDX) | The improved version of VHD with larger capacity and better performance. |
Backups in the VHD and VHDX formats cannot be restored with O&O DiskImage. They can only be mounted as virtual drives. Use the O&O DiskImage format for backups you want to restore.
Check that the chosen format is compatible with the systems on which you need to access the backup files.
Encryption
Encrypt backup with password on the backup page protects the backup with a password. Keep the password in a safe place: an encrypted backup cannot be restored without it.
Validation
Under Settings > Validation, enable Validate backup after completion to check every finished backup for integrity. The check reads the backup file and compares its structure with the expected data, so errors that occurred during the backup are found early.
Validation takes additional time, depending on the size and location of the backup file. Enable it at least for important backups. A backup can also be checked later with Tools > Check backup; see Tools.
Report
Under Settings > Report, enable Create report to record every backup operation with its time, the files involved, the space used and any errors. Reports help you to monitor backups and to analyze problems. See Reports and logs.