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sys.dm_database_replica_states (Azure SQL Database)

Applies to: Azure SQL Database Azure SQL Managed Instance

Returns state information for each database that participates in primary and secondary replicas. On a secondary replica, returns one row for every secondary database on the instance. On the primary replica, returns one row for the primary database, and an additional row for each secondary database.

Important

Depending on the action and higher-level states, database-state information may be unavailable or out of date. Furthermore, the values have only local relevance.

Column name Data type Description (on primary replica)
database_id int Identifier of the database.

In Azure SQL Database, the values are unique within a single database or an elastic pool, but not within a logical server.
group_id uniqueidentifier Identifier of the availability group to which the database belongs.
replica_id uniqueidentifier Identifier of the availability replica within the availability group.
group_database_id uniqueidentifier Identifier of the database within the availability group. This identifier is identical on every replica to which this database is joined.
is_local bit Whether the availability database is local, one of:

0 = The database isn't local to the SQL Server instance.

1 = The database is local to the server instance.
is_primary_replica bit Returns 1 if the replica is primary, or 0 if it is a secondary replica in the availability group to which the database belongs. This doesn't refer to the primary or secondary database in a distributed availability group or an active geo-replication relation.

Applies to: SQL Server 2014 (12.x) and later versions.
synchronization_state tinyint Data-movement state, one of the following values.

0 = Not synchronizing. For a primary database, indicates that the database isn't ready to synchronize its transaction log with the corresponding secondary databases. For a secondary database, indicates that the database hasn't started log synchronization because of a connection issue, is being suspended, or is going through transition states during startup or a role switch.

1 = Synchronizing. For a primary database, indicates that the database is ready to accept a scan request from a secondary database. For a secondary database, indicates that active data movement is occurring for the database.

2 = Synchronized. A primary database shows SYNCHRONIZED in place of SYNCHRONIZING. A synchronous-commit secondary database shows synchronized when the local cache says the database is failover ready and is synchronizing.

3 = Reverting. Indicates the phase in the undo process when a secondary database is actively getting pages from the primary database.

Important: When a database on a secondary replica is in the REVERTING state, forcing failover to the secondary replica leaves the database in a state in which it can't be started as a primary database. Either the database needs to reconnect as a secondary database, or you need to apply new log records from a log backup.

4 = Initializing. Indicates the phase of undo when the transaction log required for a secondary database to catch up to the undo LSN is being shipped and hardened on a secondary replica.

Important: When a database on a secondary replica is in the INITIALIZING state, forcing failover to the secondary replica leaves the database in a state in which it can't be started as a primary database. Either the database needs to reconnect as a secondary database, or you need to apply new log records from a log backup.
synchronization_state_desc nvarchar(60) Description of the data-movement state, one of:

- NOT SYNCHRONIZING
- SYNCHRONIZING
- SYNCHRONIZED
- REVERTING
- INITIALIZING
is_commit_participant bit 0 = Transaction commit isn't synchronized with respect to this database.

1 = Transaction commit is synchronized with respect to this database.

For a database on an asynchronous-commit availability replica, this value is always 0.

For a database on a synchronous-commit availability replica, this value is accurate only on the primary database.
synchronization_health tinyint Reflects the intersection of the synchronization state of a database that is joined to the availability group on the availability replica and the availability mode of the availability replica (synchronous-commit or asynchronous-commit mode), one of the following values.

0 = Not healthy. The synchronization_state of the database is 0 (NOT SYNCHRONIZING).

1 = Partially healthy. A database on a synchronous-commit availability replica is considered partially healthy if synchronization_state is 1 (SYNCHRONIZING).

2 = Healthy. A database on a synchronous-commit availability replica is considered healthy if synchronization_state is 2 (SYNCHRONIZED), and a database on an asynchronous-commit availability replica is considered healthy if synchronization_state is 1 (SYNCHRONIZING).
synchronization_health_desc nvarchar(60) Description of the synchronization_health of the availability database.

- NOT_HEALTHY
- PARTIALLY_HEALTHY
- HEALTHY
database_state tinyint 0 = Online
1 = Restoring
2 = Recovering
3 = Recovery pending
4 = Suspect
5 = Emergency
6 = Offline

Note: Same as the state column in sys.databases.
database_state_desc nvarchar(60) Description of the database_state of the availability replica.

- ONLINE
- RESTORING
- RECOVERING
- RECOVERY_PENDING
- SUSPECT
- EMERGENCY
- OFFLINE

Note: Same as the state_desc column in sys.databases.
is_suspended bit Database state, one of:

0 = Resumed
1 = Suspended
suspend_reason tinyint If the database is suspended, the reason for the suspended state, one of:

0 = User action
1 = Suspend from partner
2 = Redo
3 = Capture
4 = Apply
5 = Restart
6 = Undo
7 = Revalidation
8 = Error in the calculation of the secondary-replica synchronization point
suspend_reason_desc nvarchar(60) Description of the database suspended state reason, one of:

SUSPEND_FROM_USER = A user manually suspended data movement

SUSPEND_FROM_PARTNER = The database replica is suspended after a forced failover

SUSPEND_FROM_REDO = An error occurred during the redo phase

SUSPEND_FROM_APPLY = An error occurred when writing the log to file (see error log)

SUSPEND_FROM_CAPTURE = An error occurred while capturing log on the primary replica

SUSPEND_FROM_RESTART = The database replica was suspended before the database was restarted (see error log)

SUSPEND_FROM_UNDO = An error occurred during the undo phase (see error log)

SUSPEND_FROM_REVALIDATION = Log change mismatch is detected on reconnection (see error log)

SUSPEND_FROM_XRF_UPDATE = Unable to find the common log point (see error log)
recovery_lsn numeric(25,0) On the primary replica, the end of the transaction log before the primary database writes any new log records after recovery or failover. For a given secondary database, if this value is less than the current hardened LSN (last_hardened_lsn), recovery_lsn is the value to which this secondary database would need to resynchronize (that is, to revert to and reinitialize to). If this value is greater than or equal to the current hardened LSN, resynchronization would be unnecessary and wouldn't occur.

recovery_lsn reflects a log-block ID padded with zeroes. It isn't an actual log sequence number (LSN).
truncation_lsn numeric(25,0) On the primary replica, for the primary database, reflects the minimum log truncation LSN across all the corresponding secondary databases. If local log truncation is blocked (such as by a backup operation), this LSN might be higher than the local truncation LSN.

For a given secondary database, reflects the truncation point of that database.

truncation_lsn reflects a log-block ID padded with zeroes. It isn't an actual log sequence number.
last_sent_lsn numeric(25,0) The log block identifier that indicates the point up to which all log blocks have been sent by the primary. This is the ID of the next log block that will be sent, rather than the ID of the most recently sent log block.

last_sent_lsn reflects a log-block ID padded with zeroes. It isn't an actual log sequence number.
last_sent_time datetime Time when the last log block was sent.
last_received_lsn numeric(25,0) Log block ID identifying the point up to which all log blocks have been received by the secondary replica that hosts this secondary database.

last_received_lsn reflects a log-block ID padded with zeroes. It isn't an actual log sequence number.
last_received_time datetime Time when the log block ID in last message received was read on the secondary replica.
last_hardened_lsn numeric(25,0) Start of the Log Block containing the log records of last hardened LSN on a secondary database.

On an asynchronous-commit primary database or on a synchronous-commit database whose current policy is "delay", the value is NULL. For other synchronous-commit primary databases, last_hardened_lsn indicates the minimum of the hardened LSN across all the secondary databases.

Note: last_hardened_lsn reflects a log-block ID padded with zeroes. It isn't an actual log sequence number.
last_hardened_time datetime On a secondary database, time of the log-block identifier for the last hardened LSN (last_hardened_lsn). On a primary database, reflects the time corresponding to minimum hardened LSN.
last_redone_lsn numeric(25,0) Actual log sequence number of the last log record that was redone on the secondary database. last_redone_lsn is always less than last_hardened_lsn.
last_redone_time datetime Time when the last log record was redone on the secondary database.
log_send_queue_size bigint The amount of log records of the primary database that hasn't been sent to the secondary databases, in kilobytes (KB).
log_send_rate bigint Average rate at which primary replica instance sent data during last active period, in kilobytes (KB)/second.
redo_queue_size bigint The amount of log records in the log files of the secondary replica that hasn't yet been redone, in kilobytes (KB).
redo_rate bigint Average rate at which the log records are being redone on a given secondary database, in kilobytes (KB)/second.

redo_rate is calculated by dividing the total log bytes redone since database engine startup by the time span when redo was actively running, rather than by the elapsed time. Because redo may not be running continuously, resulting value may be different (higher) than the value of Database Replica:Redone Bytes/sec performance counter.
filestream_send_rate bigint The rate at which the FILESTREAM files are shipped to the secondary replica, in kilobytes (KB)/second.
end_of_log_lsn numeric(25,0) Local end of log LSN. Actual LSN corresponding to the last log record in the log cache on the primary and secondary databases. On the primary replica, the secondary rows reflect the end of log LSN from the latest progress messages that the secondary replicas have sent to the primary replica.

end_of_log_lsn reflects a log-block ID padded with zeroes. It isn't an actual log sequence number.
last_commit_lsn numeric(25,0) Actual log sequence number corresponding to the last commit record in the transaction log.

On the primary database, this corresponds to the last commit record processed. Rows for secondary databases show the log sequence number that the secondary replica has sent to the primary replica.

On the secondary replica, this is the last commit record that was redone.
last_commit_time datetime Time corresponding to the last commit record.

On the secondary database, this time is the same as on the primary database.

On the primary replica, each secondary database row displays the time that the secondary replica that hosts that secondary database has reported back to the primary replica. The difference in time between the primary-database row and a given secondary-database row represents approximately the recovery point objective (RPO), assuming that the redo process is caught up and that the progress has been reported back to the primary replica by the secondary replica.
low_water_mark_for_ghosts bigint A monotonically increasing number for the database indicating a low water mark used by ghost cleanup on the primary database. If this number isn't increasing over time, it implies that ghost cleanup might not happen. To decide which ghost rows to clean up, the primary replica uses the minimum value of this column for this database across all availability replicas (including the primary replica).
secondary_lag_seconds bigint The number of seconds that the secondary replica is behind the primary replica during synchronization.

Applies to: SQL Server 2016 (13.x) and later versions.
quorum_commit_lsn numeric(25,0) Identified for informational purposes only. Not supported. Future compatibility isn't guaranteed.
quorum_commit_time datetime Identified for informational purposes only. Not supported. Future compatibility isn't guaranteed.

Permissions

Requires VIEW DATABASE STATE permission on the database.

See also