What are you running? Exchange?? Redundancy is nice, but email back-ups are futile. Backups might save from most, but not all lost messages after a crash.
Anyway, before we divert to a some other topic, someone please answer the question for the simplest case - we've already decided that every RAID controller in the world cannot be trusted: Now SATA controller - no cache, SATA disk - write-back cache disabled. FFS mounted 'sync' on it. In most cases, can rename() provide the quarantee as its man page? By most cases I mean typical usage day-to-day usage without single-bit or other errors, or hardware going flaky. I do know errors happen, ok? Thanks!