Re: problem with mfiutil

On Fri, Aug 06, 2010 at 06:58:29PM +0200, Ian FREISLICH wrote:
> John Baldwin wrote:
> > On Friday, August 06, 2010 7:32:00 am Ian FREISLICH wrote:
> > > Hi
> > > 
> > > I'm unable to make a raid10 on my servers with 6 disks in each
> > > stripe.  I tried a few ways:
> > > 
> > > ~ # mfiutil -u1 create raid10 -s1M e1:s0,e1:s1,e1:s2,e1:s3,e1:s4,e1:s5 
> > e1:s6,e1:s7,e1:s8,e1:s9,e1:s10,e1:s11
> > > mfiutil: Command failed: Invalid parameter
> > > mfiutil: Failed to add volume: Input/output error
> > > 
> > > ~ # mfiutil -u1 create raid10 -s1M 19,29,18,26,22,20 31,30,21,27,28,32
> > > mfiutil: Command failed: Invalid parameter
> > > mfiutil: Failed to add volume: Input/output error
> > > 
> > > It does however work with 2 disks in each stripe:
> > > ~ # mfiutil -u1 create raid10 -s1M 19,29 31,30
> > > 
> > > any ideas?
> > 
> > Yes, you have it inverted.  You are creating a stripe across a bunch of 
> > RAID-1's and you need to list all the RAID-1's, so something like this:
> > 
> > mfiutil -u 1 create raid10 -s 1M 19,31 29,39 18,21 26,27 22,28 20,32
> 
> Hmm.  I'll give that a try, but it's not the way the controler
> configured it fyrom the BIOS utility.  It was definitely a mirror
> of 2 6 disk stripes.  The controller is a Perc 6/E.

What you described is RAID 0+1, not RAID 10.  Typically in RAID 0+1 you
make two stripes, each with half the disks, and then mirror them.  RAID
10 you make lots of mirrored drive pairs and then stripe across all the
mirrors.  RAID 10 has higher redundancy and lower rebuild times than 0+1

Regards,

Gary