Fault Tolerant refers to systems capable of uptimes of 99.999% or higher. RAID disks, multi-pathing, RAIN Networking are some technologies in use in fault tolerant systems that can continue operation during a failure.

System backups are NOT part of a fault tolerant plan per se but, are required in a fault tolerant system in case of a complete failure. System backups should always be kept outside of the fault tolerant environment.

P. N Marinos has written:

'A simulator for reliability predictions of fault-tolerant system architectures' -- subject(s): Redundancy (Engineering), Fault-tolerant computing

COMPUTERS, LRT's

RAID 1 is the most fault tolerant, as all drives have to fail to lose data.

Raymond S. Lim has written:

'Fault-tolerant computing' -- subject(s): Fault-tolerant computing