Information Technology Reference
In-Depth Information
was famous for its fault-tolerant systems. Its systems were equipped with
two pieces of every component (CPU cards, mirrored disks, etc.), linked
in a parallel setup, almost like two identical systems in one box, arranged
as primary and backup.
Fault-tolerant systems are difficult to make, and even more difficult to
maintain. Their costs can also be high. Their cost versus benefits is also
questionable (what if the backup also component fails?). It is easier to
implement fault tolerance in software than in hardware, but the problems
are similar.
