Role
- One node takes the Primary role. Usually all other nodes have a Secondary role. If a node’s role is Resolving then that node may be down.
- The failover mode for each node is configured by the DBA in the SQL Server Management Studio.
- When the failover mode is set to manual an accompanying icon highlights that manual failover is required. When no failover is available this icon is red.
Synchronization Health
Synchronization Health is indicative of the health of the node. A warning is shown for a partially healthy node. An error is shown for an unhealthy node. For the health of the Availability Group as a whole see Synchronization Health at the top of the page.
Availability mode
The availability mode is Synchronous or Asynchronous Commit as configured by the DBA in the SQL Server Management Studio.
Connected / Disconnected
The node with the Primary role is always Connected. Nodes with a Secondary role in a Connected state are available for connection. Nodes with a Secondary role in a Disconnected state are not available for connection.
Backup priority
The backup priority is a numeric value between 1 and 100 configured by the DBA in the SQL Server Management Studio.
Read-only routing URL
The read only routing URL is not the endpoint URL. Read-only routing refers to the ability of SQL Server to route qualifying read-only connection requests to an available Always On readable secondary replica.
The READ_ONLY_ROUTING_URL = ‘TCP://system-address:port’ where the system address is a string such as a system name, a fully qualified domain name, or an IP address, that unambiguously identifies the destination computer system. The port is a port number that is used by the Database Engine of the SQL Server instance.