Functions and Processes in Service Design P4

Availability Management

Introduction

• The goal of availability management is to ensure that the level of service availability delivered in all services is matched to or exceeds the current and future agreed needs of the business, in a cost effective manner.

• The objectivesare:

• Creating and maintaining an up-to-date availability plan that reflects the current and future needs of the customer.

• Advising on availability-related issues.

• The objectivesare:

• Guiding the customer and IT service provider.

• Ensuring that availability results meet or exceed the defined requirements.

• Providing assistance in diagnosis and resolution of availability-related incidents and problems.

• Assessing the impact of changes have on the availability plan and the performance and capacity of the services and resources.

• Taking proactive measures to improve availability.

• Scope

• Availability management includes designing, implementing, measuring, managing and improving IT services and the components availability.

• Must understand the service and component availability requirements from the business perspective in terms of the:

• Current business processes (their operation and requirements).

• Future business plans and requirements.

• Service targets and the current Service Operation and delivery.

• Scope

• Must understand the service and component availability requirements from the business perspective in terms of the:

• IT infrastructure, data, applications and the environment (including performance).

• Business impacts and priorities and relation to the services and their usage.

• Availability management is able to ensure that all services and components are designed and delivered in order to meet their targets in terms of agreed business need.

• Scope

• Availability management should be applied to all operational services, new, modified and supporting services.

• It covers all service aspects that have an impact on availability, such as training, competencies, procedures and tools.

• Value for the business

• The availability and reliability of IT services has a direct impact on customer satisfaction and company reputation.

• Availability management is vital.

• It should therefore be included (just like capacity management) in all stages of the Service Lifecycle.

Activities, methods and techniques

• The main activities of availability management are

• Determining the availability requirements of the business.

• Determining the Vital Business Functions (VBFs).

• Determining the impact of failing components.

• Defining the targets for availability, reliability and maintainability of the IT components.

• Monitoring and analyzing IT components.

• The main activities of availability management are

• Establishing measures and reporting of availability, reliability, and maintainability that reflects the business user and IT support organization perspectives.

• Investigating the underlying reasons for unacceptable availability.

• Creating and maintaining an availability plan.

• Availability management monitors, measures, analyzes and reports on the following aspects:

• Availability

• The service, component or CIs ability to perform its agreed function when required.

• Reliability

• The length of time a service, component or CI can perform its agreed function without interruption.

• Maintainability

• How quickly and effectively a service, component or CI can be restored to normal working after a failure.

• Availability management monitors, measures, analyzes and reports on the following aspects:

• Serviceability

• The ability of an external IT service provider to meet the terms of their contract.

• Measuring is extremely important. It can be done from three perspectives:

• Business perspective

• Looks at IT availability in terms of its contribution to or impact on the Vital Business Functions that drive the business operation.

• Measuring is extremely important. It can be done from three perspectives:

• User perspective

• View the availability of IT services as a combination of three factors:

• Frequency.

• Duration and scope of impact (how many users or organization parts are affected).

• Response times.

• The IT service provider’s perspective

• Considers IT service and component availability in regard to availability, reliability and maintainability.

• Availability management must ensure all services meet their agreed targets.

• New or changed services must be designed in such a way that they will meet their agreed targets.

• To achieve this, availability management can perform reactive and proactive activities:

• Reactive activities are executed in the operational phase of the lifecycle:

• Monitoring, measuring, analyzing and reporting the availability of services and components.

• Unavailability analysis.

• The expanded incident lifecycle.

• Service Failure Analysis (SFA).

• To achieve this, availability management can perform reactive and proactive activities:

• Proactive activities must be executed in the design phase of the lifecycle:

• Identifying Vital Business Functions.

• Designing for availability.

• Component Failure Impact Analysis (CFIA).

• Single Point of Failure (SPOF) analysis.

• Fault Tree Analysis (FTA).

• Modeling.

• Risk analysis and management.

• Availability testing schedule.

• To achieve this, availability management can perform reactive and proactive activities:

• Proactive activities must be executed in the design phase of the lifecycle:

• Planned and preventive maintenance.

• Production of the Projected Service Availability (PSA) document.

• Continual review and improvement.

• Starting points for availability management

• Other metrics for measuring availability include:

• Mean Time Between Failures (MTBF)

• The average time that a CI or service can perform its agreed function without interruption.

• Mean Time Between Service Incidents (MTBSI)

• The mean time from when a system or service fails, until it next fails.

• Mean Time To Repair (MTTR)

• The average time taken to repair a CI or service after a failure. MTTR is measured from when the CI or service fails until it is repaired.

• MTTR does not include the time required to recover or more.

• Redundancy

• A way of increasing reliability and sustainability of systems. ITIL defines the following redundancy types:

• Active redundancy

• This type is used to support essential services that absolutely cannot be interrupted.

• The productive capacity of redundancy assets is always available.

• With active redundancy all redundant units are operating simultaneously.

• For example, mirrored disks in a server computer.

• Passive redundancy

• The use of redundant assets that are left inoperative until the event of a failure (reactive).

• For example, stand-by servers or clustered systems.

Interface

• Relationshipswith other functions and processors are:

• Availability management supports incident and problem management to resolve availability incidents and problems.

• Availability management provides capacity management with resilience and spare capacity.

• Availability management provides IT Service Continuity Management (ITSCM)with assessment on the impact and risks for the business and of restore mechanisms.

• Relationshipswith other functions and processors are:

• Availability management assists SLMin determining the availability objectives and studies, and makes improvement proposals in the event of service and component failures.

• The inputsof availability management is:

• Business information, such as organization strategies, (financial) plans and information on the current and future requirements of IT services.

• Risk analyses, business impact analyses and studies of Vital Business Functions.

• The inputsof availability management is:

• Service information from the service portfolio and service catalogue and from the SLM process.

• Change calendars and release schedules from change management and release management service targets.

• Unavailability and failure information.

• The outputsof availability management is:

• The Availability Management Information System (AMIS).
  
  • The availability plan.


• The outputsof availability management is:


• Availability and recovery design criteria


• Reports on the availability, reliability and maintainability of services.


• Updated risk register.


• Monitoring, management and reporting.


• Availability management test schedule.


• Planned and preventive maintenance schedule.


• Projected Service Outage (PSO).

Metrics

• Organizations can use various KPIsto measure the effectiveness and efficiency of availability management, such as:


• Percentage reduction in the unavailability of services and components.


• Percentage increase in the of reliability of services and components.


• Percentage improvement in overall end-to-end availability of service.


• Percentage reduction of the cost of unavailability.


• Percentage increase in customer satisfaction.

Implementation

• Availability management has the following challenges:
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  • Meeting the expectations of customers, the business and the management.
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  • Integrating all availability information into an availability management information system.
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  • Convincing the business and management of the need to invest in proactive availability measures.
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  • Critical success factors for availability management are:


• Managing the availability and reliability of IT services.


• Availability of IT infrastructure (as agreed in the SLAs) provided at optimal costs.


• Satisfying business needs for access to IT services.


• Risksfor availability management are:


• Lack of commitment from the business to the availability management process.


• Lack of adequate information on plans and strategies for the future.


• Lack of resources and funds.


• Increasing labor-intensive reporting.

Source by : OGC