A common mistake by DBAs for missing to check whether all the functionality of tools are working when a SQL Server Cluster environment is setup, though you may not catch hold of few issues with basic failover/failback testing initially but when the application is initiated and data is stored with relevant scheduled jobs and processes the nodes funcationality may be different to each other. So in this case it is a best practice to document and perform a failover once the application usage is in peak...(
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Read the complete post at http://sqlserver-qa.net/blogs/tools/archive/2007/10/10/cluster-resource-sql-server-sql-server-instance-name-in-resource-group-cluster-group-name-failed.aspx