Once upon a time, George N. White III <gnwiii(a)gmail.com> said:
Some data can be replaced, but there are also real-time data flows
where data are lost forever when the system does down. I recall a
lost-of-data incident where the system was on UPS+ generator but
IT hadn't received the replacement for a failed UPS battery in the
network closet.
Lots of the time, UPSes and generators are not actively monitored and
tested. An untested backup system is not a backup system, it's just
another point of failure! I have seen failures of big UPSes,
generators, transfer switches... you name it, even if it is "redundant",
it can (and will) still fail.
--
Chris Adams <linux(a)cmadams.net>