WARNING: Server 'EX2010-DR' failed to be started as a member of database
availability group 'DAG-01'. Error: A server-side database availability group
administrative operation failed. Error: The operation failed. CreateCluster
errors may result from incorrectly configured static addresses. Error: An error
occurred while attempting a cluster operation. Error: Node ex2010-dr is
already joined to a cluster. [Server: EX2010-02.fabrikam.com]
WARNING: The operation wasn't successful because an error was encountered. You
may find more details in log file
Start-DatabaseAvailabilityGroup failed to start server(s) 'EX2010-DR' in databa
se availability group 'DAG-01'.
+ CategoryInfo : InvalidArgument: (:) [Start-DatabaseAvailability
+ FullyQualifiedErrorId : 8D6C2942,Microsoft.Exchange.Management.SystemCon
One of the reasons why this error is generated could be because of the previous un-successful execution of the command. During the previous attempt the Start-DatabaseAvailabilitygroup will change the start-up type of the Cluster Service to automatic and will fail to complete the process due to various other issues. So when executing the command again, it will assume that the node is already part of the cluster and will fail with the above error.
So Open the Services window and ensure that the cluster service is in Stopped and Disabled Status.
Re-run the command again once you ensure that the start-up type disabled and service is not running, the execution should finish successfully.
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