[Sunhelp] SSA 112

[Lara Matthews]

Hi

I am confused again.  Either I have read this wrong or two replies are
not the same.

So here goes

Magnus Abrante wrote:
> 
> +---+
> |   | <--- supposed to be a disk
> +---+
> 
> If you have RAID 0+1 you create some RAID 0 volumes and then mirror between
> them:
> 
> +---+                +---+
> |   |                |   |
> +---+                +---+
> |   | <-- RAID 1 --> |   |
> +---+                +---+
> |   |                |   |
> +---+                +---+
> RAID 0               RAID 0

So if I have 14 disks and I create one strip across 7 and then another
strip across the other 7 then mirror these strips I have 0+1 - Yes??

> 
> --
> 
> In RAID 1+0 however, you mirror on disk level instead of volume level, and
> then RAID 0 the mirrors(well, kind of).
> 
> +---+                +---+
> |   | <-- RAID 1 --> |   |
> +---+                +---+
> |   | <-- RAID 1 --> |   |
> +---+                +---+
> |   | <-- RAID 1 --> |   |
> +---+                +---+
> RAID 0               RAID 0
> 
> Basicly RAID 1+0 is more secure, since you dont loose an entire RAID 0
> in case of a disk failure, you really want this if you are mirroring
> big RAID 0's with many disks.

No this one loses me entirely.  You mirror the disks and then stripe
across the mirrors.
I have 14 disks I mirror each disk to another and then create a stripe
of the mirrored volumes d0 d1 etc.?

Am I getting warm?

Thanks for your patience

Lara