As users start to rely on virtual machines for hosting critical workloads, they become more concerned about maintaining predictable service availability in a virtualized environment. Hosting multiple workloads on a single system inherently increases the overall risk of failure, because when "all the eggs are put in one basket", the server becomes a single point of failure that has the ability to bring down all workloads at once.

Virtual machine platforms may therefore provide functions that can increase the reliability of workloads hosted in a virtualized environment by reducing downtime, both planned and unplanned. These include server resiliency functions, which helps reduce downtime resulting from hardware issues; live transfer of virtual machines over the network, during which clients perceive no interruption in their network connections; and fully functional High Availability (HA) cluster options that can reliably detect when a failure occurs at any level of a system and take responsive action that is guaranteed to restore service.

Click on one of the links below to see how the studied virtual machine platforms compare for supporting these availability features:

	Resiliency Functions (16 ratings)
	Virtual Machine Migration (8 ratings)