Synchronous replication is the process of copying data over a storage area network (SAN), local area network (LAN) or wide area network (WAN) so there are multiple up-to-date copies of the data.
Synchronous replication writes data to the primary and secondary sites at the same time so that the data remains current between sites. Synchronous replication is more expensive than other forms of replication, introduces latency that slows down the primary application and only works over distances up to 300 km.
Synchronous replication is often used for disaster recovery purposes. It is preferred for applications with low recovery time objectives (RTOs) that can't tolerate data loss.
Synchronous replication can be contrasted with asynchronous replication, a process where there is a delay before data is copied to a secondary site.
Back to: Glossary