I think I found the issue. If you're using a local listener definition in the spfile, the local instance will not register properly with the scan listener. I removed the local listener parameter in the spfile and restarted the database and it registered properly with the scan listener. I can now connect to an individual instance using the instance_name definition of the individual nodes through the scan listener.
Normally it should be possible to specify local_listener as per Note 823587.1 : "Using Oracle 11g Release 2 Real Application Clusters with Oracle E-Business Suite Release 12".
Regards, Carlo den Otter.
I agree, but it didn't seem to work using the scan listener. There is very little information in that article concerning the use of the scan listener. It details creating a listener on port 1522 and using the local listeners values. I've done this many times on 11i and now R12 with success. Never tried with the scan listener till now.
When I removed the spfile definition, the database created the values dynamically and registered the proper services with the scan listener. It would not do this with the values set in the spfile. The dynamic values are the same as I had in the spfile. It just wouldn't register with scan.