Is fault-tolerant system used to implement system backups?

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.