Synthetic cumulative incremental backups

A synthetic backup can be a synthetic full or a synthetic cumulative incremental backup.

The images that are used to create the synthetic image are known as component images. For instance, the component images in a synthetic full are the previous full image and the subsequent incremental images.

The scenario to create a synthetic, cumulative incremental backup is similar to the scenario to create a synthetic full backup. Remember, a cumulative incremental backup includes all changes since the last full backup.

If a cumulative incremental backup exists that is newer than the last full backup, a synthetic cumulative backup image is produced by consolidating the following component backup images:

All differential incremental backups that were taken since the last cumulative backup.
The last cumulative incremental backup. If no cumulative incremental backup is available, only the differential incremental backups are used for the synthetic image.

Figure: Creation of synthetic cumulative backups illustrates the creation of synthetic cumulative incremental backups (A, B, C) from the latest cumulative incremental backup and shows the subsequent differential incremental backups.

Figure: Creation of synthetic cumulative backups

The following is an example of a synthetic cumulative backup:

Create a Standard or MS-Windows policy for the clients (5.0 or later) you want to back up. Include the following schedules:
- A schedule for one full, traditional backup to run at least once.
- A schedule for daily (Monday through Saturday) differential incremental backups.
- A schedule for weekly cumulative incremental synthetic backups.
Make certain that the traditional full backup runs. If the backup does not complete, run the backup manually.
Per schedule, run daily differential incremental backups for the clients throughout the week. The last incremental for the week runs on Saturday.
Per schedule, run synthetic cumulative incremental backups for the clients on subsequent Sundays.

Note:

The synthetic cumulative backups in the scenario are only as current as the Saturday incremental backup.