PerformancePoint error after adding new servers to the farm

I was adding two front end servers to a SharePoint farm this week, and I got an error in all the dashboards when the load balancer redirect to these two servers:

PerformancePoint Services could not connect to the specified data source. Verify that either the current user or Unattended Service Account has read permissions to the data source, depending on your security configuration. Also verify that all required connection information is provided and correct.

System.Data.SqlClient.SqlException: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)

at System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject)

at System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection)

at System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject)

at System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection)

at System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)

at System.Data.SqlClient.SqlConnection.Open()

at System.Data.SqlClient.SqlConnection.Open()

at Microsoft.PerformancePoint.Scorecards.DataSourceProviders.SqlTabularDataSourceProvider.GetConnection()

at Microsoft.PerformancePoint.Scorecards.DataSourceProviders.SqlTabularDataSourceProvider.GetConnection()

at Microsoft.PerformancePoint.Scorecards.DataSourceProviders.SqlTabularDataSourceProvider.GetConnection()

at Microsoft.PerformancePoint.Scorecards.DataSourceProviders.SqlTabularDataSourceProvider.GetDataSetInternal(Int32 maximumRows)

PerformancePoint Services error code 201.

And finally I found the solution here http://social.msdn.microsoft.com/forums/en-US/sqldataaccess/thread/c488cf76-2515-440f-b3f8-9cfad689c5b6/

I’m just posting the URL in my blog to make sure that I will find it again as it helped me a lot, it has all the possible places to check.

Also you have to see if the servers are configured for Kerberos delegation if you have it, and the claims to windows token service account has the right permission on the servers as per this document http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=23176, and check the user groups on the servers to make sure that the service accounts are in the right place. you can also check the binding in the ISS and make sure that the required applications are running. Also check the web.config and the e-mail settings in iis (6)