How synchronous SnapMirror handles network issues

If SnapMirror encounters any network issues that restrict the operation of synchronous replication, SnapMirror goes into the asynchronous mode.

Normally, the source and destination systems communicate with each other periodically. If a network failure disrupts the communication, SnapMirror initiates the following process:

1. SnapMirror sets the replication to the asynchronous mode.
2. In the asynchronous mode, the source system tries to communicate with the destination system once a minute.
3. When the source system reestablishes the communication with the destination system, the source system asynchronously replicates data to the destination.
4. SnapMirror gradually transitions the replication relationship to the synchronous mode.