Moving My Install From Single Disk To Raid 1 Disks

If you want a quick run down as to WHY I want to do this, read here

Basically, my ISP could not get my server running stable on a simple raid 1 (or raid 5) so what it came down to was having them install my system on a single disk. I don't exactly like this, main reason being, if the system (or HDD) crashes, I'll end up with another several hours of down time... So here is my proposal:

Please Note: This will have to be accomplished on a live System (full backups!) over ssh as I don't trust my ISP to do things right as described in my post above.

Current Setup:
CentOS 5.3 x86_64
Dual Xeon 5410
16GB RAM
4x 750GB HDDs

/boot - /dev/sda1 - 512MB (real 471MB) ext3
/ - /dev/sda2 - 50GB (real 46GB) ext3
/home - /dev/sda3 - remaining space (real 642GB) ext3

swap - /dev/sdb1 - 32GB
/backup - /dev/sdb2 - remaining space (real 659GB) ext3

/dev/md0 - /dev/sdc + /dev/sdd - raid 1 (NOTE: uses entire disk, no partitions!)

Proposed Solution:

Code:
vgcreate -s 64M vg0 /dev/md0

lvcreate -L 512M -n lvboot vg0
lvcreate -L 50G -n lvroot vg0
lvcreate -L 5G -n lvtmp vg0
lvcreate --extent 100%FREE -n lvhome vg0

mkfs -t ext3 -m 1 /dev/vg0/lvboot
mkfs -t ext3 -m 1 /dev/vg0/lvroot
mkfs -t ext3 -m 1 /dev/vg0/lvtmp
mkfs -t ext3 -m 1 /dev/vg0/lvhome
Now, I'd like to 'init 1' at this stage but I can't, so I won't (possible solutions?? Possible to umount the / partition??)

Assuming I'd have to do this on a fully live system, I'd disable all services that I can

Code:
/etc/init.d/sendmail stop
/etc/init.d/postfix stop
/etc/init.d/saslauthd stop
/etc/init.d/httpd stop
/etc/init.d/mysql stop
/etc/init.d/courier-authlib stop
/etc/init.d/courier-imap stop
/etc/init.d/amavisd stop
/etc/init.d/clamd stop
/etc/init.d/pure-ftpd stop
/etc/init.d/fail2ban stop
/etc/init.d/syslogd stop
Then we copy all of our data from the single partitions to the raid disks

Code:
mkdir /mnt/newroot
mkdir /mnt/newroot/boot
mkdir /mnt/newroot/tmp
mkdir /mnt/newroot/home

Code:
mount /dev/vg0/lvboot /mnt/newroot/boot
mount /dev/vg0/lvroot /mnt/newroot/root
mount /dev/vg0/lvtmp /mnt/newroot/tmp
mount /dev/vg0/lvhome /mnt/newroot/home
(I think I covered everything)

Code:
umount -l /dev/sda1 (/boot)
umount -l /dev/sda3 (/home)
cp -dpRx /* /mnt/newroot/
mount /dev/sda1 /boot
cp -dpRx /boot/* /mnt/newroot/boot/
mount /dev/sda3 /home
cp -dpRx /home/* /mnt/newroot/home/
Once we have everything copied, update /etc/fstab and /etc/mtab to reflect the changes we made:
vi /etc/fstab

Code:
LABEL=/home /home ext3 defaults 0 3
LABEL=/ / ext3 defaults,usrquota,grpquota 1 1
LABEL=/boot /boot ext3 defaults 1 2
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
LABEL=SWAP-sdb1 swap swap defaults 0 0
To

Code:
/dev/vg0/lvhome /home ext3 defaults 0 3
/dev/vg0/lvroot / ext3 defaults,usrquota,grpquota 1 1
/dev/vg0/lvboot /boot ext3 defaults 1 2
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
LABEL=SWAP-sdb1 swap swap defaults 0 0
Moving on, we make a fail safe in the event this doesn't work out:
vi /boot/grub/menu.lst

find

Code:
default=0
add after

Code:
fallback=1
Then we find (in the same file):

Code:
title CentOS (2.6.18-164.el5)
root (hd1,0)
kernel /vmlinuz-2.6.18-164.el5 ro root=/dev/vg0/vgroot
initrd /initrd-2.6.18-164.el5.img
Add before:

Code:
title CentOS (2.6.18-164.el5)
root (hd3,0)
kernel /vmlinuz-2.6.18-164.el5 ro root=/dev/sda2
initrd /initrd-2.6.18-164.el5.img
Where (hd3,0) is /dev/sdc. If the system fails to boot to the raid then it'll auto boot to the single disk (/dev/sda)

then update my ramdisk:
mv /boot/initrd-`uname -r`.img /boot/initrd-`uname -r`.img_bak
mkinitrd /boot/initrd-`uname -r`.img `uname -r`

And now to set up grub...

Code:
grub
> root (hd0,0)
> setup (hd0)
we should see something like this:
Checking if "/boot/grub/stage1" exists... no
Checking if "/grub/stage1" exists... yes
Checking if "/grub/stage2" exists... yes
Checking if "/grub/e2fs_stage1_5" exists... yes
Running "embed /grub/e2fs_stage1_5 (hd0)"... 15 sectors are embedded.
succeeded
Running "install /grub/stage1 (hd0) (hd0)1+15 p (hd0,0)/grub/stage2 /grub/grub.conf"... succeeded
Done.


Code:
> root (hd3,0)
> setup (hd3)
Again, we should see something like this:
Checking if "/boot/grub/stage1" exists... no
Checking if "/grub/stage1" exists... yes
Checking if "/grub/stage2" exists... yes
Checking if "/grub/e2fs_stage1_5" exists... yes
Running "embed /grub/e2fs_stage1_5 (hd1)"... 15 sectors are embedded.
succeeded
Running "install /grub/stage1 (hd1) (hd1)1+15 p (hd1,0)/grub/stage2 /grub/grub.conf"... succeeded
Done.

Code:
> quit
From here I think we're ready to reboot, can't see where I missed anything. If all goes well then I should see my volume groups listed in 'df- h'