Description
Occurs when databases inside an Availability Group states are synchronized. For example when a database receives a fail-over request the primary becomes synchronized and the secondaries shift into their preferred state (read-only, synchronizing, etc)
Resolved by
DBAs
Suggested solutions
- Some values are expected, if values are excessively high investigate SQL Server error log
Additional research
AlwaysOn Availability Groups Troubleshooting and Monitoring Guide