Full Answer
What is availability in the ITIL framework?
In the ITIL training framework, availability is determined by three key aspects: Reliability, Maintainability, and Serviceability. Reliability is the measure of how long a service can perform without interruption. Maintainability is the measure of how quickly a failed service can be restored.
What is meant by availability?
Availability –the ability of the service or component to provide the agreed-upon functionality when required. You will find it expressed in percentage (%), e.g. service has availability of 99.95 %. It is calculated as follows:
What is Availability Management in software testing?
Availability management is about monitoring, measuring, analyzing and reporting of the following aspects: Availability –the ability of the service or component to provide the agreed-upon functionality when required. You will find it expressed in percentage (%), e.g. service has availability of 99.95 %.
What is the difference between serviceability and maintainability?
Maintainability is the measure of how quickly a failed service can be restored. Serviceability is the measure of how effectively third party suppliers deliver their services. These aspects of availability management are discussed in most online ITIL trainings and may be common knowledge to the IT service owner.
What Is Service Availability?
There are different types of services. Commonly, physical stores in your locality, like a shopping center or a cinema, are open only for certain hours in a day. Whereas things like hospitals, websites, etc. provide service throughout the day. The IT world never sleeps.
Availability Metrics
To know where you stand on service availability, you need stats. While building a system, you decide on certain availability benchmarks the system should meet. But to know if it’s happening in reality, you need to monitor some metrics. Here are the four most important service availability metrics to monitor.
Service-Level Agreement
A service-level agreement (SLA) is an agreement between the service provider and the service receiver (customer). An SLA basically contains all the terms and conditions for the association of service. Typically, it contains the following:
Improving Service Availability
As mentioned earlier, we don’t live in a perfect world. And that leaves room for improvement. Here are some tips to improve service availability:
Monitoring Availability
Service availability is no joke. Any compromise with availability has serious effects on business. You can’t just come in once a year and collect values from metrics and expect to build a highly available system. Service availability needs continuous monitoring and clarity on data. Service availability might sound like a simple thing to do.
What is serviceability in business?
Serviceability – the ability of a third party to fulfill obligations expressed in agreed levels of availability, reliability and maintainability. Using these measurements, you can assure that your suppliers are performing as agreed.
Is availability management important in ITIL?
In case this has not been stated clearly enough, availability management supports and forms an integral part of many other processes in ITIL. That increases the importance of measurements on which availability management relies heavily. It is true that “if you don’t measure it – you can’t improve it,” but more interestingly, “if you don’t measure it – you probably don’t care,” which is dangerous from a revenue point of view.
What is service availability?
Service availability is the main factor in customer satisfaction and the success of the business. If a customer is dissatisfied with the availability of IT services, it can result in loss of business to competitors. The following benefits are provided by availability management:
What is availability management?
Availability Management in ITIL is the ability of a configuration item or IT Service to perform its agreed function when required. Availability is determined by reliability, maintainability, serviceability, performance, and security. It is the duty of availability management to make sure that the level of availability that is delivered in all the IT services fulfills the availability needs in a manner that is both timely and cost-effective. Its main concern is to meet the present and future availability needs of the business.
What is the job of a monitor?
Monitor, measure, analyze, report, and review the availability of services and components.
How many levels of availability management are there?
There are two interconnected levels that complete availability management.
What is the measure of how quickly and effectively a service, component, or configuration item can be restored to normal service?
A measure of how quickly and effectively a service, component, or configuration item can be restored to normal service after experiencing a failure is called maintainability.
What is the ability of a service, component, or configuration item to perform its agreed function when required?
The ability of a service, component, or configuration item to perform its agreed function when required is called availability.
Can the shortfalls in providing the required levels of availability be recognized easily?
The shortfalls in providing the required levels of availability can be recognized easily, and the necessary actions can be taken to correct them.
What is availability testing?
Testing for availability means running an application for a planned period of time, collecting failure events and repair times, and comparing the availability percentage to the original service level agreement. Where reliability testing is about finding defects and reducing the number of failures, availability testing is primarily concerned ...
Why is high availability important?
Here, the business ideal is a continuous flow of information — and any interruption costs the company money; hence, creating high-availability applications becomes an important business strategy.
Why is my application running so slowly?
Applications often run slowly because of competition for resources such as CPUs, memory, disk I/O, and network bandwidth. When an application service must wait for hardware to become available in order to complete the task, or when several background events are occurring simultaneously, your application may run slowly.
What to do before deploying a new application?
Before deploying your new application, make sure that the catastrophic recovery procedures you have created work as expected. Is the recovery team ready? They must be trained, equipped, and well-rehearsed. How do you know it is ready unless you test it? It is one thing to perform data backups and write a disaster recovery plan, but if you cannot actually do disaster recovery, the plan is useless.
How does high availability help?
Like reliability, high-availability is certainly helped by choosing the right hardware and software technology infrastructure; there is no doubt that certain technology design choices are crucial to building a high-availability application.
Why are applications always evolving?
Applications are always evolving to fit new business requirements and improve behavior. Even mission-critical applications change over time. Because the change control process is a large source of downtime-causing errors, you had better test and validate all of the change control procedures.
Do all web applications require 24/7 uptime?
Realistically, not all applications require 24/7 uptime with instantaneous response. Some applications can fail with no consequence. Other applications can tolerate unplanned downtime but may require varying recovery strategies, while still others must provide very high availability using standby replication strategies to guarantee instant, transparent recovery with virtually no perceivable downtime.