Analysis of Methods for Providing Availability and Accessibility of Cloud Services

The article describes methods for dealing with reliability and fault tolerance issues of cloud datacenters. These methods are mainly focused on the elimination of single point of failure within any component of the cloud infrastructure, including the availability of infrastructure and accessibility of cloud services. The methods for providing the availability of hardware, software and network components are also presented. The analysis of the actual accessibility of the cloud services and the matching of cloud datacenter infrastructure with the level of reliability according to the Tier Classification System is described. Non-compliance of the actual accessibility with the level of High Availability for cloud web services was found.