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Value to the business. The Availability Management process ensures that the availability of systems and services matches the evolving agreed needs of the business



The Availability Management process ensures that the availability of systems and services matches the evolving agreed needs of the business. The role of IT within the business is now pivotal. The availability and reliability of IT services can directly influence customer satisfaction and the reputation of the business. This is why Availability Management is essential in ensuring IT delivers the right levels of service availability required by the business to satisfy its business objectives and deliver the quality of service demanded by its customers. In today’s competitive marketplace, customer satisfaction with service(s) provided is paramount. Customer loyalty can no longer be relied on, and dissatisfaction with the availability and reliability of IT service can be a key factor in customers taking their business to a competitor.

The Availability Management process and planning, just like Capacity Management, must be involved in all stages of the Service Lifecycle, from Strategy and Design, through Transition and Operation to Improvement. The appropriate availability and resilience should be designed into services and components from the initial design stages. This will ensure not only that the availability of any new or changed service meets its expected targets, but also that all existing services and components continue to meet all of their targets. This is the basis of stable service provision.

4.4.4 Policies/principles/basic concepts

The Availability Management process is continually trying to ensure that all operational services meet their agreed availability targets, and that new or changed services are designed appropriately to meet their intended targets, without compromising the performance of existing services. In order to achieve this, Availability Management should perform the reactive and proactive activities illustrated in Figure 4.13.

Figure 4.13 The Availability Management process

The reactive activities of Availability Management consist of monitoring, measuring, analysing, reporting and reviewing all aspects of component and service availability. This is to ensure that all agreed service targets are measured and achieved. Wherever deviations or breaches are detected, these are investigated and remedial action instigated. Most of these activities are conducted within the Operations stage of the lifecycle and are linked into the monitoring and control activities, Event and Incident Management processes. (See the Service Operation publication.)

The proactive activities consist of producing recommendations, plans and documents on design guidelines and criteria for new and changed services, and the continual improvement of service and reduction of risk in existing services wherever it can be cost-justified. These are key aspects to be considered within Service Design activities.



An effective Availability Management process, consisting of both the reactive and proactive activities, can ‘make a big difference’ and will be recognized as such by the business, if the deployment of Availability Management within an IT organization has a strong emphasis on the needs of the business and customers. To reinforce this emphasis, there are several guiding principles that should underpin the Availability Management process and its focus:

  • Service availability is at the core of customer satisfaction and business success: there is a direct correlation in most organizations between the service availability and customer and user satisfaction, where poor service performance is defined as being unavailable.
  • Recognizing that when services fail, it is still possible to achieve business, customer and user satisfaction and recognition: the way a service provider reacts in a failure situation has a major influence on customer and user perception and expectation.
  • Improving availability can only begin after understanding how the IT services support the operation of the business.
  • Service availability is only as good as the weakest link on the chain: it can be greatly increased by the elimination of Single Points of Failure (SPoFs) or an unreliable or weak component.
  • Availability is not just a reactive process. The more proactive the process, the better service availability will be. Availability should not purely react to service and component failure. The more events and failures are predicted, pre-empted and prevented, the higher the level of service availability.
  • It is cheaper to design the right level of service availability into a service from the start rather than try and ‘bolt it on’ subsequently. Adding resilience into a service or component is invariably more expensive than designing it in from the start. Also, once a service gets a bad name for unreliability, it becomes very difficult to change the image. Resilience is also a key consideration of ITSCM, and this should be considered at the same time.

The scope of Availability Management covers the design, implementation, measurement and management of IT service and infrastructure availability. This is reflected in the process description shown in Figure 4.13 and described in the following paragraphs.

The Availability Management process has two key elements:

  • Reactive activities: the reactive aspect of Availability Management involves the monitoring, measuring, analysis and management of all events, incidents and problems involving unavailability. These activities are principally involved within operational roles.
  • Proactive activities: the proactive activities of Availability Management involve the proactive planning, design and improvement of availability. These activities are principally involved within design and planning roles.

Availability Management is completed at two inter-connected levels:

  • Service availability: involves all aspects of service availability and unavailability and the impact of component availability, or the potential impact of component unavailability on service availability
  • Component availability: involves all aspects of component availability and unavailability.

Availability Management relies on the monitoring, measurement, analysis and reporting of the following aspects:

Availability: the ability of a service, component or CI to perform its agreed function when required. It is often measured and reported as a percentage:

(Agreed Service Time (AST) – downtime)

Availability (%) = ------------------------------------------------------- X 100 %





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