[mythtv-users] Question re: available SATA ports and linux software RAID

[Alex Butcher]

On Fri, 8 Apr 2011, Simon Hobson wrote:

> You shouldn't need a RAID calculator - though of course if you aren't
> familiar with the technology then it's probably easier than
> remembering how to do it.
> Striping - you just add up the drives (no redundancy)

Actually, /fractional/ (or negative, depending on how you see it) redundancy
- you are dependent on /all/ the drives continuing to work properly for any
of the array's contents to be readable.

> Whether to keep a spare is up to you - there isn't a stock answer. If
> you go with RAID6 then I don't think it would be worthwhile. With
> RAID5 it's a case of how long do you think it would take to get a new
> drive ?

FYI, in an 8 disc array at work built with WD400YR drives, I went through a
period about 3 years after purchase where I was getting a failure every week
or two.  The sixth drive has just failed, just after the 5 year point.

Best Regards,
Alex