MultiMartDataSource, Services Reporting not working

Question

Hi everyone,
I've been in a long battle to get Reporting working again after I migrated 2012 to SP1 to R2 and then migrated the DW server to a new server with a new hostname all in about a month.
I finally got most reports working, except the Services ones. I had to manually set all Data Sources in Reporting Services, this works fine for all the reports only needing DWDataMart, but the Services reports also need "MultiMartDatasource" which
DB is this?
I've pretty much tried connecting that data source to every SCSM DB, even the Analysis Services DWASDataBase but I can't get that to connect, which probably is expected.
Perhaps my error is due to something completely different, but I obviously want this Data Source to be correct regardless.
So which DB is the MultiMartDatasource?
This is the actual error:
System.Exception: An error has occurred during report processing. ---> System.Exception: Query execution failed for dataset 'ServiceKPIDataset'. ---> System.Exception: For more information about this error navigate to the report server on the local server
machine, or enable remote errors
   --- End of inner exception stack trace ---
   --- End of inner exception stack trace ---
   at Microsoft.Reporting.WinForms.ServerReport.ServerUrlRequest(Boolean isAbortable, String url, Stream outputStream, String& mimeType, String& fileNameExtension)
   at Microsoft.Reporting.WinForms.ServerReport.InternalRender(Boolean isAbortable, String format, String deviceInfo, NameValueCollection urlAccessParameters, Stream reportStream, String& mimeType, String& fileNameExtension)
   at Microsoft.Reporting.WinForms.ProcessingThread.ProcessThreadMain(Object arg)
System.Exception: Query execution failed for dataset 'ServiceKPIDataset'. ---> System.Exception: For more information about this error navigate to the report server on the local server machine, or enable remote errors
   --- End of inner exception stack trace ---
System.Exception: For more information about this error navigate to the report server on the local server machine, or enable remote errors
Thanks!

Answer 1

Ok, ended up install a new DW server, with new DBs using the default names and this time it created the MultiMartDataSource. So all good. For anyone else coming across this with similiar issues, I'd probably recommend setting up a new DW server as well,
with the original DB names.
But here is the connection string for the MutltiMartDatasource if you want to try and go down that road. I think some Stored Procedures might still look for the default names though and you will have other issues, even with this string:
<root><source id='DWDataMart' connectionString='Data Source=Server\SQLinstance,1436;Initial Catalog=DWDataMart;Integrated Security=True' /><source id='OMDataMart' connectionString='Data Source=Server\SQLinstance,1436;Initial Catalog=OMDWDataMart;Integrated
Security=True' /><source id='CMDataMart' connectionString='Data Source=Server\SQLinstance,1436;Initial Catalog=CMDWDataMart;Integrated Security=True' /></root>