HP WBEM Services Software Developer's Kit for HP-UX Provider and Client Developer's Guide A.01
Schema Design and Implementation
Schema Design
Chapter 3 31
Schema Design
The schema design process begins once required information and
capabilities have been identified. The first prerequisite is to define use
models. It is important to understand what information and capabilities
clients require, and also how they support given tasks. If such
information is unavailable, these requirements may come from an
external view of what information is correctly exposed via a standard (for
example SNMP or DMI), a command line interface (CLI), an application
program interface (API), or an internal view of what information and
capabilities exist for the managed resources.
A second prerequisite is to determine data sources for the management
information and control points from which a provider can implement
desired functions. Within this context meaningful schema design can
begin.
The schema design process can be viewedas a process consisting of seven
(7) steps:
• STEP 1: Define High-Level Client-Use Models
• STEP 2: Draft Object Model
• STEP 3: Consult DMTF Model
• STEP 4: Identify Properties and Methods
• STEP 5: Finalize Schema Details
• STEP 6: Write MOF Files
• STEP 7: Optimize
For further reference, DMTF also has a simple set of steps for schema
design defined in the CIM tutorial at http://www.dmtf.org/education/.
STEP 1: Define High-Level Client-Use Models
In developing a schema, it is not enough to simply understand what data
is available. Of greater importance is understanding how an end user
would use the data in a management application. A thorough analysis
and understanding of how an end user and associated administrative
client application will use the management data will usually result in a
simpler, more useful schema.