The illustration shows four server pools: Sales, ERP, HR, and Free.
In the Sales server pool there are four servers that run an Oracle RAC database. The Sales server pool supports all workloads that use the Sales service.
The ERP server pool contains one server running an instance of an Oracle RAC database. The ERP server pool supports all workloads that use the AP and AR services.
The HR server pool contains two servers that run instances of the same Oracle RAC database as the ERP server pool. The ERP server pool supports all workloads that use the HR and OS services.
The Free server pool contains a single server, managed by Oracle Clusterware. The server does not have an Oracle RAC database running on it.
Underlying all the Oracle RAC database instances, server pools, and servers, including the server in the Free server pool, is Oracle Clusterware.
End of Description.