SAMPLE WF CONFIG FOR NLB SCENARIO
If you are deploying your workflow application to multiple machines(NLB scenario) and all these machines are using same database for persistence , you need to use following config
(1)OwnershipTimeoutSeconds should be very high value ,so other hosts can't load these workflows
(2)Disable auto unload
SAMPLE WORKFLOW CONFIG:
<WorkflowRuntime Name="WorkflowServiceContainer">
<CommonParameters>
<add name="ConnectionString" value="Initial Catalog=SHARED;Data Source=localhost;Integrated Security=SSPI;"/>
</CommonParameters>
<Services>
<add type="System.Workflow.Runtime.Hosting.ManualWorkflowSchedulerService, System.Workflow.Runtime, Version=3.0.00000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add type="System.Workflow.Activities.ExternalDataExchangeService, System.Workflow.Activities, Version=3.0.00000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" ConfigurationSection="ExternalDataExchange"/>
<add type="System.Workflow.Runtime.Hosting.SqlWorkflowPersistenceService, System.Workflow.Runtime, Version=3.0.00000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" UnloadOnIdle="false" OwnershipTimeoutSeconds="5000" LoadIntervalSeconds="0" />
<add type="System.Workflow.Runtime.Hosting.DefaultWorkflowCommitWorkBatchService, System.Workflow.Runtime, Version=3.0.00000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
<add type="System.Workflow.Runtime.Tracking.SqlTrackingService, System.Workflow.Runtime, Version=3.0.00000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" IsTransactional="false"/>
</Services>
</WorkflowRuntime>
AFTER WE ARE DONE WITH WORKFLOW, WE CAN CALL THIS METHOD TO UNLOAD WORKFLOW MANUALLY:
StateMachineWorkflowInstance stateInstance = new StateMachineWorkflowInstance(Application["WorkflowRuntime"] as WorkflowRuntime, instanceId);
stateInstance.WorkflowInstance.Unload();
