Convert / root filesytem to use lvm over raid

I have outlined below the steps taken to move from a normal single disk system and convert to a raid1 using an additional drive:

Note: /boot cannot be on lvm nor any other raids other than raid1 partition.

Don't forget to make the essential backups prior.

Convert / to raid/lvm

1. fdisk /dev/sdb and make clone of sda (convert partition type to "Linux raid autodetect")
   
2. add /dev/sdb1 -- /boot - 13 blocks (100Mb) - type raid
   
3. add /dev/sdb2 -- rest - type raid
   
4. Create raid partitions:
   
   partprobe
mdadm -C /dev/md0 --auto=yes -l 1 -n 2 missing /dev/sdb1
mdadm -C /dev/md1 --auto=yes -l 1 -n 2 missing /dev/sdb2

5. Create logical volume and copy / partition and /dev files over:
   
   pvcreate /dev/md1
vgcreate vg0 /dev/md1
lvcreate -L 4G -n lv0 vg0
mke2fs -j /dev/vg0/lv0
mkdir /mnt/lv0
mount /dev/vg0/lv0 /mnt/lv0
find / -xdev | cpio -pvmd /mnt/lv0
cp -aux /dev /mnt/lv0

6. Edit /mnt/lv0/etc/fstab to reflect the new root
   
   /dev/vg0/lv0            /                       ext3    defaults        1 1

7. Chroot to new filesystem an create initrd with raid and lvm support
   
   chroot /mnt/lv0
mount -t proc /proc /proc
mount -t sysfs /sys /sys
vgscan
vgchange -ay
mkinitrd -v /boot/initrd-2.6.18-92.1.6.el5.lvm.img 2.6.18-92.1.6.el5

8. Edit grub.conf to point to new root /dev/vg0/lv0
   
9. reboot

Convert /boot to raid1

1. Upon successful reboot
   
2. Create file-system and copy /boot partition files over:
   
   mke2fs -j /dev/md0
mkdir /mnt/md0
mount /dev/md0 /dev/mnt0
cp -aux /boot/* /mnt/md0
umount /mnt/md0
umount /boot

3. fdisk /dev/sda and change the type for /dev/sda1 to raid autodetect
   
4. Add /dev/sda1 to /dev/md0 raid
   
   partprobe
mdadm /dev/md0 -a /dev/sda1

5. Edit /etc/fstab to reflect new /boot
   
   /dev/md0 /boot ext3 defaults 1 2

6. Mount /boot
   
   mount /boot

7. failover setup for /boot
   
   # grub
grub> root (hd1,0)
grub> setup (hd1)
grub> root (hd0,0)
grub> setup (hd0)
grub> find /boot/grub/stage1 {to confirm}
   (hd0,0)
   (hd1,0)
grub> quit

8. Edit /etc/grub.conf
   
   title CentOS-LVM-HD0 (2.6.18-92.1.6.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-92.1.6.el5 ro root=/dev/vg0/lv0 console=tty0 console=ttyS1,19200n8
        initrd /initrd-2.6.18-92.1.6.el5.lvm.img
title CentOS-LVM-HD1 (2.6.18-92.1.6.el5)
        root (hd1,0)
        kernel /vmlinuz-2.6.18-92.1.6.el5 ro root=/dev/vg0/lv0 console=tty0 console=ttyS1,19200n8
        initrd /initrd-2.6.18-92.1.6.el5.lvm.img

9. Reboot
   
   shutdown -r now

Create swap on raid1 and add sda2 to raid1:

1. Create logical volume swap.
   
   swapoff -a
lvcreate -L 4G -n lv-swap vg0
mkswap -L SWAP-md1  /dev/vg0/lv-swap

2. Edit /etc/fstab with the new swap and turn swap on:
   
   LABEL=SWAP-md1   swap   swap    pri=0,defaults        0 0
swapon -a

3. fdisk /dev/sda and create sda2 as raid autodetect:
   
   partprobe
mdadm /dev/md1 -a /dev/sda2