High Availability IT Services examines the considerations for designing and running highly available "services" and not just the systems infrastructure that supports those services. In doing so, it introduces the concept of logical outages and human factors. Providing an overview of virtualization, cloud computing, and cloud vendors, it supplies a detailed look at availability, redundancy, and fault tolerance. The book examines high availability architectures such as reliability, availability, and serviceability; clusters; grids; and redundant arrays of independent disks storage.