Availability replica is disconnected

THIS TOPIC APPLIES TO: yesSQL ServernoAzure SQL DatabasenoAzure SQL Data Warehouse noParallel Data Warehouse


Policy Name Availability Replica Connection State
Issue Availability replica is disconnected.
Category Critical
Facet Availability replica


This policy checks the connection state between availability replicas. The policy is in an unhealthy state when the connection state of the availability replica is DISCONNECTED. The policy is otherwise in a healthy state.


For this release of SQL Server 2017, information about possible causes and solutions is located at Availability replica is disconnected on the TechNet Wiki.

Possible Causes

The secondary replica is not connected to the primary replica. The connected state is DISCONNECTED. This issue can be caused by the following:

  • The connection port might be in conflict with another application.

  • The encryption type or algorithm is mismatched.

  • The connection endpoint has been deleted or has not been started.

  • The transport is disconnected.

Possible Solutions

Following are possible solutions for this issue:

  • Check the database mirroring endpoint configuration for the instances of the primary and secondary replica and update the mismatched configuration.

  • Check if the port is conflicting, and if so, change the port number.

See Also

Overview of Always On Availability Groups (SQL Server)
Use the Always On Dashboard (SQL Server Management Studio)