Providing Open Architecture High Availability Solutions

4.0 Customer Requirements for Open HA Systems

For many years computers have been controlling systems that provide critical services where

continuous availability and data integrity are essential. The scale, the availability requirements, and

the level of data integrity vary widely across the spectrum of such services. Consequently, the

techniques and implementations that provide the high availability (HA) are also equally varied.

However, the history and evolution of these applications has added extra dimensions of complexity

and variance to the HA implementations. Often the development has been ad hoc and narrowly

focused, and has usually led to proprietary solutions that are fragile and expensive to support.

Much of the same technology has been re-invented time and time again, but in ways that are

incompatible and impossible to reuse.

With the widespread adoption of open systems and more horizontally-focused component

suppliers, there is growing expectation for an open system approach to provide products and

services that address the needs of high availability in a variety of application spaces.

An Open System HA Framework Can:

• Standardize the design of commonly used HA components and techniques

• Encourage the development of Commercial-Off-The-Shelf (COTS) HA components

• Allow competitive environment to improve product features, cost, and performance

• Allow application developers to focus on core value-add development

• Reduce the HA application development time and cost, and improve its supportability

• Improve the portability of HA applications between hardware platforms, operating systems

and middleware

• Improve the overall reliability of systems and applications by leveraging the HA component

testing over a wider installed base

• Provide a consistent basis for comparing the HA features offered in different systems

• Improve the supply of staff with relevant HA technology experience

When formulating the direction and definition of such an open systems approach, it is important to

consider the range of applications, and the scope of their requirements. This section identifies some

of the application areas considered for an open systems HA framework architecture, and reviews at

a high level the requirements, expectations, and desirable features that typical applications may

have for an HA framework.