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williamsnr

@optonline.net

mirror a raid setup

theres 3 drives in raid (the one with parity drive)

can i add another drive that will be the mirror of whatever the first raid is doing? at the hardware level?

is that possible?


psafux
Premium,VIP
join:2005-11-10
kudos:2
Raid 6 offers striped (raid 0) + dual parity so you could essentially lose two drives out of the array before having to replace and rebuild. (4 drives)

Raid 0+1 is similar. A striped array is mirrored. (4 drives)

Raid 3 & Raid 4 are also striped with dedicated parity with a minimum of 3 disks. The more drives you add, the better efficiency and parity offered.

Most 'basic' hardware raid controllers probably wouldn't offer these RAID types - doublecheck before purchasing.

You can read up on any of these and the other RAID configurations using Google / Wikipedia, etc.


Jahntassa
What, I can have feathers
Premium
join:2006-04-14
Conway, SC
kudos:4
reply to williamsnr
I don't think there's a RAID 5+1 controller if that's what you're asking (dual matching RAID 5 arrays in a mirror).

I also don't think there are any hardware RAID controllers that will support RAID5 mirrored onto a single non-RAID drive.


psafux
Premium,VIP
join:2005-11-10
kudos:2
I would concur.


Karride
Slower Traffic Keep Right
Premium
join:2000-04-17
Germantown, TN
reply to Jahntassa
said by Jahntassa:

I don't think there's a RAID 5+1 controller if that's what you're asking (dual matching RAID 5 arrays in a mirror).

I also don't think there are any hardware RAID controllers that will support RAID5 mirrored onto a single non-RAID drive.
I guess you could layer software RAID 1 on top of the hardware RAID5 and the single disk...But I imagine you would take a pretty ugly performance hit, not to mention creating "complicated plumbing"


psafux
Premium,VIP
join:2005-11-10
kudos:2
OP specifically requested hardware level solution.

ChiTang
Premium,MVM
join:2002-08-23
Alhambra, CA
kudos:1
reply to williamsnr
3 HDs in a RAID and 1 HD to mirror the RAID. It does not exist at any HW level.

If it is for redundancy, may consider a RAID + hot spare.

IMO, RAID is not a replacement/substitute of backup.

Any redundancy method without constant monitoring will end up failing at the last line of defense.
--
I used to be indecisive, now I am not sure.