Retention Policy in Server Edition

In the Server edition, you can select the logic behind the short-term retention policy. Veeam Agent offers the following options:

• Veeam Agent retains restore points for the last N days; the number of days is defined by the user. In this case, Veeam Agent works in a similar way as in the Free or Workstation editions. To learn more, see Retention Policy in Free and Workstation Editions.
• Veeam Agent retains the number of latest restore points defined by the user.

During every backup job session, Veeam Agent checks if there is any obsolete restore point in the backup chain. If some restore point is obsolete, it is removed from the chain.

When removing obsolete restore points, Veeam Agent for Microsoft Windows does not simply delete backup files from disk. It transforms the backup chain so that the backup chain always contains a full backup file on which subsequent incremental backup files are dependent. To maintain the consistency of the backup chain, Veeam Agent for Microsoft Windows uses the following rotation scheme:

1. During every backup job session Veeam Agent for Microsoft Windows adds a backup file to the backup chain and checks if there is an obsolete restore point.

2. If an obsolete restore point exists, Veeam Agent for Microsoft Windows transforms the backup chain. As part of this process, it performs the following operations:

1. Veeam Agent for Microsoft Windows re-builds the full backup file to include in it data of the incremental backup file that follows the full backup file. To do this, Veeam Agent for Microsoft Windows injects into the full backup file data blocks from the earliest incremental backup file in the chain. This way, a full backup ‘moves’ forward in the backup chain.

2. The earliest incremental backup file is removed from the chain as redundant: its data has already been injected into the full backup file, and the full backup file includes data of this incremental backup file.