RAID/LVM Root Filesystem on SuSE8.2

[David Bandel]

On Tue, 08 Feb 2005 22:39:27 -0500, Matthew Carpenter <matt at eisgr.com> wrote:
> (I'm *so* sorry for the last post!  I didn't mean to hit send.  I wasn't
> done editing or describing the problems.)
> 
> Hi all,
> 
> After reading about making RAID and LVM work on your boot system (and
> foolishly misplacing the article.  Not the online one, but the one they
> didn't place online), I engaged in a little trial and error run.
> 
> I took a 30GB drive (/dev/hda) which is running my primary
> firewall/dns/dhcp for my home network, added in another 30GB drive
> (/dev/hdc) and went to town.
> First off, creating two partitions on /dev/hdc setting them to partition
> type FD (auto-raid):
> /dev/hdc1   128mb
> /dev/hdc2   28GB
> 
> Then,  creating the md0 and md1 device (I stupidly created the md0
> device as LVM and left md1 to the /boot partition)
> 
> I then created two LV's on /dev/md0:
> /dev/BigBlock/Root         (/)
> /dev/BigBlock/Active       (/var - /home is a symlink to /var/home)
> 
> Copied all the data over from /dev/hda to the appropriate partition on
> /dev/md1 (/boot) and /dev/BigBlock/(Active|Root)
> 
> I then edited /boot/grub/menu.lst, adding:
> title BigBlock-RAID
>     root (hd0,0)
>     kernel (hd0,0)/boot/vmlinuz root=/dev/BigBlock/Root console=tty1
> console=ttyS0,9600n8
>     initrd (hd0,0)/boot/initrd
> 
> To be safe, I also created /etc/mdadm.conf and /etc/raidtab.  I also
> added lvm-mod and raid1 into the initrd (which were compiled as modules
> instead of into the kernel).  SuSE allows this by adding these module
> names into /etc/sysconfig/kernel and running mkinitrd.

And here's the problem.

Please read my raid how-to.  It describes how to convert a running
system to raid.  Perhaps this is what you need to do.  Create your LVM
systems with normal disks, then go from there to raid.

Also, from what I've seen here, RAID _must_ be built into the kernel
to boot raid.  You cannot boot into raid partitions using raid
modules. At least, I've not gotten that to work.

> 
> Rebooting using this new entry kicks out the following error messages
> (many lines snipped):
> 

[many more lines snipped]

When you create the raid, a superblock will be written.  You need this done.

I suspect for your setup, you'll need LVM and RAID built into the
kernel so lvm can come up first, then the raid, then finally begin
booting off your disks.

Ciao,

David A. Bandel
-- 
Focus on the dream, not the competition.
            - Nemesis Air Racing Team motto