Availability Database Data Synchronization

Microsoft.SQLServer.Windows.Monitor.DatabaseReplica.DataSynchronizationState (UnitMonitor)

This monitor checks the data synchronization state of the database replica. The monitor is unhealthy when the data synchronization state is NOT SYNCHRONIZING or the state is not SYNCHRONIZED for a synchronous commit database replica.

Knowledge Base article:

Summary

Causes

The data synchronization state of this availability database is unhealthy. On an asynchronous-commit availability replica, every availability database should be in the SYNCHRONIZING state. On a synchronous-commit replica, every availability database should be in the SYNCHRONIZED state.

Availability replica might be disconnected
The data movement might be suspended.
The database may not be accessible.
It might be a temporary delay issue due to network latency or the load on primary or secondary replica.

Resolutions

Resolve any connection or data movement suspend issue. Check events for the issue using SSMS and find database error and follow the troubleshooting for the specific error to resolve it.

Overridable Parameters

Name	Description	Default Value
Enabled	Enables or disables the workflow.	Yes
Generates Alerts	Defines whether the workflow generates an Alert.	No
Interval (seconds)	The recurring interval of time in seconds in which to run the workflow.	900
Synchronization Time	The synchronization time is specified by using a 24-hour format. Can be omitted.
Timeout (seconds)	Specifies the time the workflow is allowed to run before being closed and marked as failed.	300
Timeout for query execution (seconds)	The workflow will fail and register an event, if the query execution takes longer than the specified period.	60
Timeout for database connection (seconds)	The workflow will fail and register an event, if it cannot access the database during the specified period.	15

Element properties:

Target

Microsoft.SQLServer.Windows.DatabaseReplica

Parent Monitor

System.Health.AvailabilityState

Category

AvailabilityHealth

Enabled

True

Alert Generate

True

Alert Severity

MatchMonitorHealth

Alert Priority

Normal

Alert Auto Resolve

True

Monitor Type

Microsoft.SQLServer.Windows.MonitorType.AlwaysOnSystemPolicy

Remotable

True

Accessibility

Public

Alert Message

MSSQL on Windows: Availability Database Data Synchronization State is not healthy

The data synchronization state is NOT SYNCHRONIZING or the state is not SYNCHRONIZED for a synchronous commit database replica.
Database Name: {3}
Instance Name: {1}
Machine Name: {0}
Availability Group Name: {2}

RunAs

Default

Source Code:

<UnitMonitor ID="Microsoft.SQLServer.Windows.Monitor.DatabaseReplica.DataSynchronizationState" Accessibility="Public" Enabled="true" Target="SqlDiscW!Microsoft.SQLServer.Windows.DatabaseReplica" ParentMonitorID="Health!System.Health.AvailabilityState" Remotable="true" Priority="Normal" TypeID="Microsoft.SQLServer.Windows.MonitorType.AlwaysOnSystemPolicy" ConfirmDelivery="false">

  <Category>AvailabilityHealth</Category>

  <AlertSettings AlertMessage="Microsoft.SQLServer.Windows.Monitor.DatabaseReplica.DataSynchronizationState.AlertMessage">

    <AlertOnState>Warning</AlertOnState>

    <AutoResolve>true</AutoResolve>

    <AlertPriority>Normal</AlertPriority>

    <AlertSeverity>MatchMonitorHealth</AlertSeverity>

    <AlertParameters>

      <AlertParameter1>$Target/Host/Host/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/MachineName$</AlertParameter1>

      <AlertParameter2>$Target/Host/Host/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/InstanceName$</AlertParameter2>

      <AlertParameter3>$Target/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DatabaseReplica"]/AvailabilityGroupName$</AlertParameter3>

      <AlertParameter4>$Target/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DatabaseReplica"]/AvailabilityDatabaseName$</AlertParameter4>

    </AlertParameters>

  </AlertSettings>

  <OperationalStates>

    <OperationalState ID="Success" MonitorTypeStateID="HealthState" HealthState="Success"/>

    <OperationalState ID="Critical" MonitorTypeStateID="ErrorState" HealthState="Warning"/>

  </OperationalStates>

  <Configuration>

    <MachineName>$Target/Host/Host/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/MachineName$</MachineName>

    <NetbiosComputerName>$Target/Host/Host/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/NetbiosComputerName$</NetbiosComputerName>

    <InstanceName>$Target/Host/Host/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/InstanceName$</InstanceName>

    <ConnectionString>$Target/Host/Host/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/ConnectionString$</ConnectionString>

    <InstanceVersion>$Target/Host/Host/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/Version$</InstanceVersion>

    <InstanceEdition>$Target/Host/Host/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DBEngine"]/Edition$</InstanceEdition>

    <MonitoringType>$Target/Host/Host/Property[Type="SqlDiscW!Microsoft.SQLServer.Windows.DBEngine"]/MonitoringType$</MonitoringType>

    <PolicyName>AlwaysOnDbrDataSynchronizationState</PolicyName>

    <BagKey>3-$Target/Property[Type="SqlCoreLib!Microsoft.SQLServer.Core.DatabaseReplica"]/AvailabilityDatabaseName$</BagKey>

    <SqlExecTimeoutSeconds>60</SqlExecTimeoutSeconds>

    <SqlTimeoutSeconds>15</SqlTimeoutSeconds>

    <TimeoutSeconds>300</TimeoutSeconds>

    <IntervalSeconds>900</IntervalSeconds>

    <SyncTime/>

  </Configuration>

</UnitMonitor>