With the Synthetic Incremental feature enabled, Rapid Recovery compares the data on a protected machine with the data that is in the previous backup stored in the repository and only sends the difference to the Core server. This significantly reduces the amount of repository space needed to store the backup and thereby reduces the amount of time needed to re-replicate or re-export that recovery point.
New synthetic incremental recovery points appear in the Rapid Recovery Core interface next to the original recovery points and with a recovery point type of “Incremental, Synthetic”.
The feature is disabled by default and can be enabled in either (1) the Rapid Recovery Core Settings page:
Or (2) individual machine protected Settings page:
NOTE: Both the Rapid Recovery Core and the Rapid Recovery Agent need to be upgraded to at least version 6.5 in order to use the feature.
The actual time to take this synthetic incremental recovery point and transfer the data to the Core server will vary, but it is expected that it can take longer than a regular incremental recovery point.
Synthetic recovery points are supported with all the types of backups and encryption that Rapid Recovery uses and supports, e.g.: agentless and agent-based backups, ESXi, Hyper-V, virtual and physical machines, Windows and Linux, encrypted recovery points etc.
ESXi agentless protection and encrypted synthetic recovery points could result in a bigger snapshot size than an agent-based backup, this is expected behavior. However, they should still be smaller than full base image backups.
Note: In some cases, like volume formatting or hardware issues, a standard base image may still occur even when Synthetic incremental feature is enabled.
Synthetic snapshot can also be forced manually from the Rapid Recovery Core user interface. The option is available next to the Incremental and Base image force snapshot buttons.