[Slackdocs] RAID howto

[Paul Chavent]

Hi Niki

On 10/14/2012 04:27 PM, Niki Kovacs wrote:
> Le 14/10/2012 13:45, Paul Chavent a écrit :
>> That why i struggle with raid since my first post. I'm looking or the
>> right way to do.
>
> Oh, and something else. There's sometimes the remnants of previous setups to take care of. So when I have to install Slackware on a server using RAID, I do the following:
>
> # mdadm -Ss
>
> # mdadm --zero-superblock /dev/sda1
> # mdadm --zero-superblock /dev/sda2
> # mdadm --zero-superblock /dev/sda3
> # mdadm --zero-superblock /dev/sdb1
> # mdadm --zero-superblock /dev/sdb2
> # mdadm --zero-superblock /dev/sdb3
> ...
Yes i do it like you.

>
> (Repeat for every disk and partition...)
>
> Once this is done, I zero the partition tables:
>
> # dd if=/dev/zero of=/dev/sda bs=512 count=64
> # dd if=/dev/zero of=/dev/sdb bs=512 count=64
> ...
Idem

>
> (Again, repeat for every disk)
>
> REBOOT!
>
> And then only:
>
> # cfdisk /dev/sda
>
> Partition every single disk: sda, sdb, sdc using "DA"
>
> And then:
>
> # mdadm --create /dev/md1 --level=1 --raid-devices=4 --metadata=0.90 /dev/sda1 /dev/sdb1 etc.
THAT THE POINT ! As you say in the previous post "I used the --metadata=0.90 option for every array: md1, md2 and md3".
Try to not use "--metadata=0.90" for non boot devices. And you will probably encounter my problem.


>
> Before launching the installer, I take care of defining the swap partition:
>
> # mkswap /dev/md2
>
> Now I do the following:
>
> # watch cat /proc/mdstat
>
> And here I wait for my disks to synchronize completely, which can take an hour and a half or more. Only when they are fully synchronized ([UUUU]) do I launch the installer:
>
> # setup
>
> Once installation is complete: EXIT the installer.
>
> # chroot /mnt
>
> Two things here:
>
> 1) Build an initrd (and don't forget RAID="1").
>
> 2) Configure LILO to use the RAID array.
>
> Hope that helps.
>
> Niki
>