Set of dedicated hypervisors that do not incorporate intrinsic backup mechanisms
One of the most real cases was the shutdown of the 3 AWS’ data centers in New Orleans during 2005 Hurricane Katrina. The effects were very important, Datacenters were stopped several days. This scenario is becoming more real even in France and Europe.
Despite precautions implemented in the Cloud (especially the Public Cloud) to put men at distances of infrastructure, unexpected error can happen. To minimize human intervention, administrators work only through controlled configuration deployment.
Recently few Clouds have had shutdowns (often related to electrical incidents or telecom interruptions) of several hours, which had impacts on some customers over 24 hours.
This scenario regularly happens and randomly affects Clients instances, stopping their IT for a few minutes to several hours.