Retention Policies

A retention policy defines for how long Veeam Backup & Replication must store restore points for replicas. Veeam Backup & Replication offers two retention policy schemes:

• Short-term retention
• Long-term retention

Short-term Retention

Veeam Backup & Replication retains short-term restore points for the number of hours or minutes specified in CDP policy settings. When the retention period is exceeded, Veeam Backup & Replication transforms the replication chain in the following way. The example shows how short-term retention works for a replica with one virtual disk.

1. Veeam Backup & Replication checks whether the replication chain contains outdated short-term restore points.
2. If an outdated restore point exists, Veeam Backup & Replication commits data for the short-term restore point from the transaction log file into the nearest technical point (TP). For more information on technical points, short-term restore points, long-term restore points and when they are created, see CDP Replication Chain.

3. If the transaction log file does not contain data for further short-term restore points, Veeam Backup & Replication deletes the transaction log file as redundant — its data has already been committed into the technical delta disk file.

4. After a technical point remains without the related transaction log file, Veeam Backup & Replication considers this technical point outdated and commits data of a newer technical point or a long-term restore point into the outdated technical point. Consider the following:

• The newer technical restore point must not have the related transaction log.
• The data of the long-term restore point can be committed into a technical point but not vice versa. Long-term restore points remain unchanged till they are retained by the long-term retention.

Long-term Retention

Veeam Backup & Replication retains long-term restore points for the number of days specified in CDP policy settings. When the retention period is exceeded, Veeam Backup & Replication transforms the replication chain in the following way. The example shows how long-term retention works for a replica with one virtual disk.

1. Veeam Backup & Replication checks whether the replication chain contains outdated long-term restore points.
2. If an outdated restore point exists, Veeam Backup & Replication rebuilds the file of an outdated long-term restore point (LT RP) to include data of a newer long-term restore point. To do that, Veeam Backup & Replication commits into the base disk file data from the earliest delta disk file that relates to a long-term restore point. This way, the base disk file ‘moves’ forward in the replication chain.

For more information on technical points, short-term restore points, long-term restore points and when they are created, see CDP Replication Chain.

3. Veeam Backup & Replication removes the earliest delta disk file from the chain as redundant — this data has already been committed into the base disk file.