The pre-requisite check script exadataDiscoveryPreCheck.pl that is bundled in Exadata plug-in 12.1.0.3 does not support the catalog.xml file. Download the latest exadataDiscoveryPreCheck.pl file from My Oracle Support as described in the “Discovery Precheck Script” section of the
If multiple database clusters share the same Exadata Storage server, in one Enterprise Manager management server environment, you can discover and monitor the first DB Machine target and all its components. However, for additional DB Machine targets sharing the same Exadata Storage server, the Oracle Exadata Storage Server Grid system and the Oracle Database Exadata Storage Server System will have no Exadata Storage server members because they are already monitored.
If the perfquery command installed in the system has version 1.5.8 or later, you will encounter a bug (ID 15919339) where most columns in the HCA Port Errors metric in the host targets for the compute nodes will be blank. If there are errors occurring on the HCA ports, it will not be reported in Enterprise Manager.
To check your version, run the following command:
perfquery -V