How Data Flows in VVR Asynchronous Mode

This section explains how VVR processes an incoming write when replicating in asynchronous mode.

Example---How Data Flows in the Asynchronous Mode of Replication

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1. VVR receives a write on the Primary.
2. Writes it to the Primary SRL.
3. On the Primary, acknowledges to the application that the write is complete.
4. Sends the writes to the asynchronous Secondary hosts, in the order in which they were received on the Primary, and at the same time, writes to the Primary data volumes.
5. When the Primary receives the network acknowledgement, it knows that the write has been received in the Secondary VVR memory buffer.
6. VVR sends the writes to the data volumes on the Secondary and then sends a data acknowledgement to the Primary.
7. When the Primary receives the data acknowledgement, VVR marks the write as complete in the SRL.