In Oracle Database 12c, Oracle Clusterware supports the management of a cluster configuration policy set as a native Oracle Clusterware feature. A cluster configuration policy contains one definition for each server pool that is defined in the system. A cluster configuration policy also specifies resource placement and cluster node availability. A cluster configuration policy set defines the names of all of the server pools that are configured in a cluster, and contains one or more configuration policies.
There is always only one configuration policy in effect at any one time. However, administrators typically create several configuration policies to reflect the different business needs and demands based on calendar dates or time of day parameters. For instance, morning hours during business days are typically when most users log in and download their email; email-related workloads are usually light at nighttime and on weekends. In such cases, you can use cluster configuration policies to define the server allocation based on the expected demand. More specifically for this example, a configuration policy that allocates more servers to OLTP workloads is in effect during workday mornings, and another configuration policy allocates more servers to batch workloads on weekends and workday evenings.
Using cluster configuration policies can also help manage clusters that comprise servers of different capabilities, such as different computer and memory sizes (heterogeneous). To create management and availability policies for clusters comprised of heterogeneous server types, the cluster administrator can create server categories based on server attributes. These attributes can restrict which servers can be assigned to which server pools. For example, if you have some servers in a cluster that run older hardware, then you can use an attribute to specify that these servers should only be allocated to the server pools that support batch jobs and testing, instead of allocating them to the server pools that are used for online sales or other business-critical applications.
See Also:
Oracle Clusterware Administration and Deployment Guide for more information