The ability of a computer system to remain operational despite various failures is?
The ability of a computer system to remain operational despite various failures is Resilience
In computer networking: resilience is the ability to provide and maintain an acceptable level of service in the face of faults and challenges to normal operation.” Threats and challenges for services can range from simple misconfiguration over large scale natural disasters to targeted attacks.
System resilience is an ability of the system to withstand a major disruption within acceptable degradation parameters and to recover within an acceptable time. Learn more in: Cyber Threats to Critical Infrastructure Protection: Public Private Aspects of Resilience.