Share via


sys.dm_hadr_availability_replica_states (Transact-SQL)

Returns a row for each local availability replica and a row for each remote availability replica in the same AlwaysOn availability group as a local replica. Each row contains information about the state of a given availability replica.

Important

To obtain information about every availability replica in a given availability group, query sys.dm_hadr_availability_replica_states on the server instance that is hosting the primary replica. When queried on a server instance that is hosting a secondary replica of an availability group, this dynamic management view returns only local information for the availability group.

Column name

Data type

Description

replica_id

uniqueidentifier

Unique identifier of the availability replica.

group_id

uniqueidentifier

Unique identifier of the availability group.

is_local

bit

Whether the availability replica is local, one of:

0 = Indicates a remote secondary replica in an availability group whose primary replica is hosted by the local server instance. This value occurs only on the primary replica location.

1 = Indicates a local availability replica. On secondary replicas, this is the only available value for the availability group to which the replica belongs.

role

tinyint

Current AlwaysOn Availability Groups role of a local availability replica or a connected remote availability replica, one of:

0 = Resolving

1 = Primary

2 = Secondary

For information about AlwaysOn Availability Groups roles, see Overview of AlwaysOn Availability Groups (SQL Server).

role_desc

nvarchar(60)

Description of role, one of:

RESOLVING

PRIMARY

SECONDARY

operational_state

tinyint

Current operational state of the availability replica, one of:

0 = Pending failover

1 = Pending

2 = Online

3 = Offline

4 = Failed

5 = Failed, no quorum

NULL = Replica is not local.

For more information, see Roles and Operational States, later in this topic.

operational_state_desc

nvarchar(60)

Description of operational_state, one of:

PENDING_FAILOVER

PENDING

ONLINE

OFFLINE

FAILED

FAILED_NO_QUORUM

NULL

recovery_health

tinyint

Rollup of the database_state column of the sys.dm_hadr_database_replica_states dynamic management view, one of:

Value

Description

0

In progress. At least one joined database has a database state other than ONLINE (database_state is not 0).

1

Online. All the joined databases have a database state of ONLINE (database_state is 0).

NULL

is_local = 0

recovery_health_desc

nvarchar(60)

Description of recovery_health, one of:

ONLINE_IN_PROGRESS

ONLINE

NULL

synchronization_health

tinyint

Reflects a rollup of the database synchronization state (synchronization_state)of all joined availability databases (also known as "database replicas") and the availability mode of the availability replica (synchronous-commit or asynchronous-commit mode). The rollup will reflect the least healthy accumulated state the databases on the availability replica.

Value

Description

0

Not healthy. At least one joined database is in the NOT SYNCHRONIZING state.

1

Partially healthy. Some replicas are not in the target synchronization state: synchronous-commit replicas should be synchronized, and asynchronous-commit replicas should be synchronizing.

2

Healthy. All replicas are in the target synchronization state: synchronous-commit replicas are synchronized, and asynchronous-commit replicas are synchronizing.

synchronization_health_desc

nvarchar(60)

Description of synchronization_health, one of:

NOT_HEALTHY

PARTIALLY_HEALTHY

HEALTHY

connected_state

tinyint

Whether a secondary replica is currently connected to the primary replica, one of:

Value

Description

0

Disconnected. The response of an availability replica to the DISCONNECTED state depends on its role, as follows:

  • On the primary replica, if a secondary replica is disconnected, its secondary databases are marked as NOT SYNCHRONIZED on the primary replica, which waits for the secondary to reconnect.

  • On a secondary replica, upon detecting that it is disconnected, the secondary replica attempts to reconnect to the primary replica.

1

Connected.

Each primary replica tracks the connection state for every secondary replica in the same availability group. Secondary replicas track the connection state of only the primary replica.

connected_state_desc

nvarchar(60)

Description of connection_state, one of:

DISCONNECTED

CONNECTED

last_connect_error_number

int

Number of the last connection error.

last_connect_error_description

nvarchar(1024)

Text of the last_connect_error_number message.

last_connect_error_timestamp

datetime

Date and time timestamp indicating when the last_connect_error_number error occurred.

Roles and Operational States

The role, role, reflects the state of a given availability replica and the operational state, operational_state, describes whether the replica is ready to process client requests for all the database of the availability replica. The following table summarizes the operational states that are possible for each role: RESOLVING, PRIMARY, and SECONDARY.

Role

Meaning of Operational States for Each Role

RESOLVING

When an availability replica is in the RESOLVING role, the possible operational states are as follows:

Operational State

Description

PENDING_FAILOVER

A failover command is being processed for the availability group.

OFFLINE

All configuration data for the availability replica has been updated on WSFC cluster and, also, in local metadata, but the availability group currently lacks a primary replica.

FAILED

A read failure has occurred during an attempt trying to retrieve information from the WSFC cluster.

FAILED_NO_QUORUM

The local WSFC node does not have quorum. This is an inferred state.

PRIMARY

When an availability replica is performing the PRIMARY role, it is currently the primary replica. The possible operational states are as follows:

Operational State

Description

PENDING

This is a transient state, but a primary replica can be stuck in this state if workers are not available to process requests.

ONLINE

The availability group resource is online, and all database worker threads have been picked up.

FAILED

The availability replica is unable to read to and/or write from the WSFC cluster.

SECONDARY

When an availability replica is performing the SECONDARY role, it is currently a secondary replica. The possible operational states are as follows:

Operational State

Description

ONLINE

The local secondary replica is connected to the primary replica.

FAILED

The local secondary replica is unable to read to and/or write from the WSFC cluster.

NULL

On a primary replica, this value is returned when the row relates to a secondary replica.

Security

Permissions

Requires VIEW SERVER STATE permission on the server.

See Also

Concepts

Overview of AlwaysOn Availability Groups (SQL Server)

Monitor Availability Groups (Transact-SQL)