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How Synthetic Full Backup Works

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    To create a synthetic full backup, Veeam Backup & Replication performs the following steps:

    1. On the day when synthetic full backup is scheduled, Veeam Backup & Replication triggers a new backup job session. During this session, Veeam Backup & Replication first performs incremental backup in a regular manner and adds a new incremental restore point to the backup chain.

    VM data for this incremental restore point is retrieved from the production storage. Incremental backup helps Veeam Backup & Replication ensure that the synthetic full backup scheduled on this day includes the latest changes of the source VM in the production environment.

    How Synthetic Full Backup Works 

    1. At the end of the backup job session, the Veeam Data Mover Service in the backup repository builds a new synthetic full backup using restore points that are already available in the backup chain, including the newly created incremental restore point.

    How Synthetic Full Backup Works 

    1. When the synthetic full backup is created, the Veeam Data Mover Service deletes the incremental restore point created at the beginning of the job session.

    As a result, you have a backup chain that consists of a full backup, set of incremental restore points and synthetic full backup.

    How Synthetic Full Backup Works 

    1. Every next job session will create a new incremental restore point starting from the synthetic full backup until the day on which synthetic full backup is scheduled. On this day, Veeam Backup & Replication will create a new synthetic full backup.

    How Synthetic Full Backup Works 

    Veeam Backup & Replication automatically triggers a backup job session to create a synthetic full backup, even if a regular backup job session is not scheduled on this day. The job session is started at the same time when the parent backup job is scheduled. For example, if you schedule the parent backup job at 12:00 AM Sunday through Friday, and schedule synthetic full backup on Saturday, Veeam Backup & Replication will start a backup job session that will produce a synthetic full backup at 12:00 AM on Saturday.

    If a regular backup job is scheduled together with a synthetic full backup, Veeam Backup & Replication will produce only one backup file — a synthetic full backup that will reflect the latest state of the source VM. An incremental restore point that should have been created by the backup job schedule will not be added to the backup chain.

    Veeam Backup & Replication creates a synthetic full backup only once a day on which it is scheduled. If you run the backup job again on the same day, Veeam Backup & Replication will perform incremental backup in a regular manner.