[UPlat] Resource State Model

[Heather Kreger <kreger@us.ibm.com>]

Reworked Resource State Model:

1.1.1 Resource State Model (was Resource Lifecycle)
1.1.1.1     What?

Resource state model is a set of states that a resource can be in and the
valid transitions between those states.  A resource goes through a set of
states and transitions throughout its life.  Resource state model
manageability provides the capability to understand the valid states and
transitions, manage the actual operational state of a resource, invoke
operations to influence a change in the state of a resources, and receive
events indicating when a state change has occurred.  .

1.1.1.2     Why?

An application or management tool uses the resource state information for a
resource to better understand and manage that resource. Resource state
awareness can be used in several ways:


1. Decorating operations and properties with state context: Some Operations
and properties may be valid only when the resource is in a particular
state. In fact, a property may have a different set of valid values when
the resource is in a particular state. The manageability capabilities of a
resource may indicate which operations or property values are valid during
particular resource states.


Invoking operations and changing properties may also influence the resource
state itself. Therefore the manageability capabilities of a resource may
indicate what the initial state must be for an operation to be invoked or
what the end state should be after the operation finishes.


Using these state decorations on operations and properties, operations of a
resource may be determined through introspection of a resource’s state to
aid the application or management tool in doing those actions only in the
state in which those actions are valid. This is important in autonomic
systems where actions taken do not expect exceptions to be thrown.


2. State management: Several management applications, including
availability management, provisioning, automated recovery, state change
impact analysis, and problem determination all need to be able to
understand the state model of a resource and influence a change in that
state.

1.1.1.3     How?

May be in the management domain and within WSDM scope, therefore not part
of the platform.


Suggestion: A specification based on GGF CMM Lifecycle

Heather Kreger
STSM, Web Services Lead Architect for SWG Emerging Technologies
Author of "Java and JMX: Building Manageable Systems"
kreger@us.ibm.com
919-543-3211 (t/l 441)  cell:919-496-9572