1.4 Managing the Lifecycle

Given that such a wide variety of functionality is provided by management systems, it may be easier to think about them in terms of what parts of the lifecycle of IT resources they manage.

Nearly all computing resources have a similar lifecycle that needs to be managed (see Figure 1.4).

Figure 1.4. The Resource Management Lifecycle

First the resource needs to be installed onto its platform. Then it needs to be started or somehow made available to those who need to use it. After it has been started, it is said to be executing. While it is executing, it needs to be monitored , operated, and configured. This is called runtime management. At some point the resource will need to be stopped to block its availability to its users. A stopped resource is "unavailable." When a resource is unavailable it can be maintained (updates and fixes) and configured. Given this generic scenario, we define the lifecycle of a resource to have the following stages:

1. Distribute . Move files that are the resource to the target system.

2. Install . Install a resource in the target system.

3. Start . Initialize a resource so that it will be executing.

4. Execute . Actively perform functions.

   • Monitor . Periodically check a resource to ensure that it is available and performing appropriately.

   • Operate . Invoke functions or operations while executing that do not permanently affect the state of the resource.

   • Configure . Permanently change configuration data while executing or while stopped.

5. Stop . Terminate a resource so that it is no longer executing.

6. Maintain . Apply code or configuration changes to a resource on a regular basis or as needed.

7. Uninstall . Remove a resource from the system.

The need to manage this lifecycle has spawned the various management disciplines. Most modern management applications provide support for one or more of these disciplines, but no single management application supports all of them.