What is asynchronous replication?
Asynchronous replication is a data storage method of backing up data over a period of time rather than immediately during or immediately after the primary storage confirms the write operation. This method results in a system with good performance and lower bandwidth requirements, but the backups are not immediately available if something happens to primary storage.
In an asynchronous replication backup system, the data is first written to primary storage. The data is then replicated to a separate remote storage medium such as magnetic tape or HD hard drives, depending on the settings and the type of implementation. The copying or replication takes place at predetermined intervals.
This method allows for good performance without impacting bandwidth usage because data is not replicated to remote backups in real time as is the case with a synchronous replication method. Data is only backed up after predetermined times. This does not guarantee 100% backup, so it should be used for less sensitive data or information with loss tolerance.
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