[ale] Recommendation for off-line storage?

[James P. Kinney III]

> took freakin' forever.  but they don't want to spring for tape
> drives/libraries b/c "it's on a raid5 system, why do we need backups" ...

Because RAID recovery when 2 drives fail is imperfect and costs more than
a decent tape backup system.

Most corps are really boneheaded about data backup. Especially the small
ones. They are the ones that have the fewest resources for recovery and
thus they get hit the hardest during drive failures. Certain types of data
MUST be kept for 10 years (Think IRS!). The company accounting data AND
THE SOFTWARE THAT RUNS IT must be available during an IRS audit. These are
things that absolutely can NOT be trusted to a single copy system. RAID5
is designed speed and data security. But it is not designed for data
archival.

I have seen too many RAID5 arrays fail because the system was built using
identical hard drive models and some even had sequential serial numbers.
This is a statistically good process of getting multiple failed drives.
RAID5 can only handle 1 dead drive at a time. If a second drive fails
dureing the recovery, the RAID stack is toast without serious, low-level
($$$) work.

A mirrored RAID5 is a better bet fro the hard-drive only crowd. Use
different drive brands for better hardware safety.