#!/bin/bash
#
# https://kamaok.org.ua/?p=182
# http://blog.ispsystem.info/2016/11/centos-68-raid1-mdadm.html
#
########################################
#

EXIT(){
    [[ -n  "${2}" ]] && echo "${2}"
    exit "${1}"
}

MSG(){
    echo "___________________________________________________"
    echo
    echo "  $*"
    echo
}

EDITOR="mcedit"

SRC="/dev/sda"
TRGT="/dev/sdb"
B="1"  # /boot
R="2"  # / (root FS)

RDEV=$(grep ^/dev/ /etc/mtab | while read -a i ; do
    [[ "${i[1]}" == "/" ]] && echo "${i[0]}" | sed "s/\//\\\\\//g"
done)

[[ -n "${RDEV}" ]] || EXIT 1 "Error: root device not found"
[[ -b "${TRGT}" ]] || EXIT 1 "Error: ${TRGT} not found"
[[ -n $(grep "^${SRC}" /etc/mtab) ]] || EXIT 1 "Error: root drive not ${SRC}"

########################################
#

sfdisk -d "${SRC}" | sfdisk --force "${TRGT}"

modprobe linear
modprobe raid0
modprobe raid1

####

MSG "Linux raid autodetect fd"

fdisk "${TRGT}"

MSG "Clear superblocks"

mdadm --zero-superblock "${TRGT}${B}"
mdadm --zero-superblock "${TRGT}${R}"

MSG "Create /dev/md${B} and /dev/md${R}"

mdadm --create /dev/md"${B}" --metadata=0.90  --level=1 --raid-disks=2 missing "${TRGT}${B}"
mdadm --create /dev/md"${R}" --metadata=0.90  --level=1 --raid-disks=2 missing "${TRGT}${R}"

mdadm --detail --scan > /etc/mdadm.conf

MSG "Mkfs /dev/md${B} and /dev/md${R}"

mkfs.ext4 /dev/md"${B}"
mkfs.ext4 /dev/md"${R}"

#### / (root FS)

MSG "Mount RootFS"

mkdir /raid
mount /dev/md"${R}" /raid/ || EXIT 1 "Mount /dev/md${R} failed"

MSG "Copy  RootFS"

cd    /
find  . -depth -xdev | grep -v '^\./tmp/' | cpio -pmd /raid/

blkid  /dev/md? >> /raid/etc/fstab
"${EDITOR}" /raid/etc/fstab

touch  /raid/.autorelabel

#### /boot

MSG "Mount boot"

mount /dev/md"${B}" /raid/boot/

MSG "Copy boot"

cd    /boot/
find  . -depth | cpio -pmd /raid/boot/

sed -i "s/"${RDEV}"/\/dev\/md"${R}"/g" /raid/boot/grub/grub.conf

# blkid  /dev/md? >> /raid/boot/grub/grub.conf

# remove rd_NO_DM rd_NO_MD
# remove VolGroup-lv_root and other
# add rd_MD_UUID=b9baa472:faeb3a7c:6e31c5b6:310ac827 ?
"${EDITOR}" /raid/boot/grub/grub.conf

# (hd0) /dev/sda
# (hd1) /dev/sdb
"${EDITOR}" /raid/boot/grub/device.map

####

mount -o bind /dev  /raid/dev
mount -o bind /sys  /raid/sys
mount -o bind /proc /raid/proc

####

MSG "Create initramfs"

mv /raid/boot/initramfs-$(uname -r).img /raid/boot/initramfs-$(uname -r).img.old
dracut --nolvmconf --mdadmconf --force /raid/boot/initramfs-$(uname -r).img $(uname -r)

MSG "Setup grub into chroot and reboot system

type:
chroot /raid/"