MCCS (Mantech Continuous Cluster Server) is a high-availability solution for mission-critical computing systems developed by Mantech.
It provides continuous computing environment due to unplanned downtime such as natural disasters, or system failures, or unexpected service interruptions caused by terrors, sabotage or a human error and minimize the downtime due to planned downtime like periodic maintenance.
Normal business of companies in our current industries is conducted in computers, and most of the core information for this needs continuous service on a 24/7 basis. Mission critical systems require no downtime server infrastructure, but you will meet many types of service failures which bring in negative business impacts. 
MCCS protects and make always on your mission critical application from these failure and disaster scenarios.