Cluster administrators must be able to carry out the following tasks:
Install and register a new version of an existing resource type
Allow the registration of multiple versions of a given resource type
Upgrade an existing resource to a new version of the resource type without having to delete and re-create the resource
A resource type that you intend to upgrade is called an upgrade-aware resource type.
Elements of an existing resource type that you might change are as follows:
Attributes of resource type properties
The set of declared resource properties, including standard and extension properties
Attributes of resource properties, such as default, min, max, arraymin, arraymax, or tunability
The set of declared methods
The implementation of methods or monitors
You do not necessarily have to modify a resource type when you modify application code.
You need to understand the requirements for providing the tools that will enable a cluster administrator to upgrade a resource type. This chapter tells you what you need to know to set up these tools.