[TriLUG] Re: New system configuration thoughts

[Lance A. Brown]

Jason Tower wrote:
> i *think* raid 6 is supported on the newer cards, but haven't really
> checked.  i know you can assign a failover drive, which yields similar
> results as long as you don't lose the second disk before the failover is
> added to the array.

Ummm, no.  RAID-5 with a failover disk isn't very similar to RAID-6.
With RAID-5, you are vulnerable to a double-disk failure from the point
the 1st disk fails until the failover disk is completely rebuilt into
the RAID-5.  With the large capacity drives we have these days that
window could be many many hours.  A 2nd failure during that rebuild
window looses all the data on the RAID

With RAID-6, you would have to loose three disks out of the RAID before
you loose the array completely and have to restore from backups [We ALL
make backups, don't we? :-)]

--[Lance]

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