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Jamie_R
11-24-02, 07:45 AM
I guy I work with mentioned this to me and I've been trying to figure out if it can be done and how:
an IDE RAID 5 - mirrored
yes 2 IDE RAIDS - w/ one mirroring the other (in the same rig).
Any Ideas? I don't know if you can have 2 hard drives on the same cable and have them in an array.
I have only dabbled a little w/ RAID, so please be gentle :)
Thanx As Always Guys!:)

YARDofSTUF
11-24-02, 03:00 PM
sounds right

zooner
11-25-02, 02:58 AM
first of all... i'm not a gooroo. jsut a normal user.

yos is right

very expensive. you cant do it with onbaord raid, you need a raid5 capable controller card. Each HD has it's own ribbon cable.

me thinks it's a waste. better off just ghosting the drives to a third HD on IDE.

Sid
11-25-02, 03:12 AM
My question is why in gods name would you want to mirror a raid 5? Its already fault tolerant by design.

zooner
11-25-02, 03:16 AM
i believe he means raid5, which is a mirrored array... that mirroring a raid5 array.

Sid
11-25-02, 03:28 AM
Raid 5 is not mirroring. Who ever told you that is wrong. Here is the definition of raid 5.

RAID-5. This type includes a rotating parity array, thus addressing the write limitation in RAID-4. Thus, all read and write operations can be overlapped. RAID-5 stores parity information but not redundant data (but parity information can be used to reconstruct data). RAID-5 requires at least three and usually five disks for the array. It's best for multi-user systems in which performance is not critical or which do few write operations.

YeOldeStonecat
11-25-02, 11:29 AM
I think what you're describing is more of a RAID 0 + 1....where you have pair A drives, striped in RAID 0, and you have another pair of drives, pair B, also striped in RAID 0. Then you take both of those pairs, and mirror them in RAID 1.

4x drives, made up of 2x striped pairs...and each of those pairs is combined into 1x mirrored.

A_old
11-25-02, 12:06 PM
Originally posted by YeOldeStonecat
I think what you're describing is more of a RAID 0 + 1....where you have pair A drives, striped in RAID 0, and you have another pair of drives, pair B, also striped in RAID 0. Then you take both of those pairs, and mirror them in RAID 1.

4x drives, made up of 2x striped pairs...and each of those pairs is combined into 1x mirrored.
:2cool: :nod:

Jamie_R
11-25-02, 08:46 PM
Thanx Guys! If it's up to me, we'll just do a RAID5 period ... or 2 mirroed IDE drives :D (keeping it simple is my middle name).

zooner
11-26-02, 12:24 AM
Raid 5 is not mirroring. Who ever told you that is wrong. Here is the definition of raid 5.

dumb me. I was tired!

You should try raid0 if you're setting up a new system. If you already have the parts, it's well worth your time. Trust me... just a couple of hours running on it and you'll NEVER go back. I tried running raid1 to be safe and I lasted a whole week before I couldnt take the speed.

We pay so much for our systems and the HD's are such a huge bottleneck. Nope, raid0 isnt going to bring the hordes of women to your door... but it's certainly more satisfying then long load times.