[mythtv-users] Reassemble RAID with mdadm

[Krzysztof Adamski]

On Thu, 2010-03-18 at 10:55 -0400, John Drescher wrote:
> On Thu, Mar 18, 2010 at 9:45 AM, Krzysztof Adamski <k at adamski.org> wrote:
> > On Wed, 2010-03-17 at 19:04 -0400, MarcT wrote:
> >
> >> My RAID 5 drive is only used for media storage, I have a raid mirror setup
> >> for the / and /boot partitions.
> >
> > I wanted to add to this, like you I have /boot as RAID1, it uses the
> > same drives that are part of the RAID6 for the media files.
> > My /boot RAID1 is a mirror of 8 drives, not 2 mirror and 6 spares, but 8
> > drives in a mirror:
> > md0 : active raid1 sdc1[0] sdf1[7] sdb1[6] sdd1[5] sde1[4] sdg1[3]
> > sda1[2] sdh1[1]
> >      240832 blocks [8/8] [UUUUUUUU]
> >
> 
> I do that on all linux raid arrays here at work.
> 
> Here is one:
> md0 : active raid1 sdh1[6](S) sdg1[5] sdf1[7](S) sde1[4] sdd1[3]
> sdc1[2] sdb1[1] sda1[0]
>       256896 blocks [6/6] [UUUUUU]
> 
> There are 2 spares here because I just added a hard drive to expand
> the image data storage lvm.
> 
> md3 : active raid5 sdh6[6] sdg6[5] sdf6[7](S) sde6[4] sdd6[3] sdc6[2]
> sdb6[1] sda6[0]
>       3540604800 blocks super 0.91 level 5, 64k chunk, algorithm 2
> [7/7] [UUUUUUU]
>       [>....................]  reshape =  2.0% (14465152/708120960)
> finish=687.2min speed=16819K/sec
> 
> This is a slower dual core so the reshape will take some time..

I get faster rebuilds with a Pentium D, check you max and min in
/proc/sys/dev/raid/speed_limit_max are higher then defaults.

K