Efficient Use of Data Centres - Factors Affecting Service Availability in Large Organisations based on IT and Data Centre Selection

IT services are an increasingly critical part of conducting business and everyday life, the IT systems and data centres that host them are also improving. The relationship between how IT systems are designed and where they are placed between an array of different data centre options makes it a challenge to plan for appropriate levels of uptime for the services being provided. The current IT landscape provides organisations to target required availability of services in an effort to reduce costs and waste while meeting there required service levels. However, reference architectures for designing IT services often fail to take the data centre into account, while the design standards of data centres typically only take the power and cooling specifications into consideration and not the configuration of the IT infrastructure or the nature of the services they host. This paper shows that by spreading a highly available IT system between data centres of various tier ratings, as opposed to placing the same highly available IT system within a standalone data centre, superior levels of service availability can be achieved while potentially utilising lower cost of data centres.