A couple of days I ago when I was working with a SQL cluster I found something interesting. I had problem with a SQL cluster, Operations Manager 2007 R2 only found the first network name in my cluster group, not the one for my SQL cluster. After some time I found the following text in the SQL management pack guide:
Having a SQL Server cluster resource group that contains more than one network name resource might mean that the clustered SQL Server resource is not monitored. For more information, see Knowledge Base article 919594.
…and KB 919594 tells you
To resolve this issue, configure existing resources in the cluster group so that System Center Operations Manager or MOM detects the virtual server, or create and configure the necessary resources. For example, you may have to create a generic application resource that does nothing. This generic application resource will enable System Center Operations Manager or MOM to discover the virtual server on which the resource is hosted.
Note If more than one Network Name resource is configured in a group, System Center Operations Manager or MOM uses the first network name that it detects as the name of the virtual server..
As soon as I had re-organized my cluster resources for SQL into a new cluster group Operations Manager 2007 R2 found the other cluster resource group and the SQL running on it. It also discovered all the SQL components for example databases and logical disks.
There is a KB article about this, KB959865, that shows you another solution, where you can do a override and enable “Multiple Servers Discovery” within the cluster MP.