Disclosed are systems and methods of synchronization between a source and a target. The synchronization relationship can be quickly and easily be created for disaster recovery, real-time backup and failover, thereby ensuring that data on the source is fully-protected at an off-site location or on another server or VM, for example, at another data center, a different building or elsewhere in the cloud. Common snapshots available on both the source and target can act as common recovery points. The common recovery points can be used to locate the most recent snapshot in common, between the source and target, to enable a delta sync of all subsequently written data at the source to the target after an offline event.