Install arch linux on btrfs raid1

arch-raid1.sh

#!/bin/bash

set -e
set -o pipefail

dd if=/dev/zero of=/dev/sda bs=1024 count=10
dd if=/dev/zero of=/dev/sdb bs=1024 count=10

RAM=$(free -m | awk '/Mem:/{print $2}')

cat > disk.sf <<EOF
label: gpt

, 512M, 21686148-6449-6E6F-744E-656564454649
; ${RAM}M, S
;
EOF

sfdisk /dev/sda < disk.sf
sfdisk /dev/sdb < disk.sf

# pacman -Sy btrfs-progs git

mkfs.btrfs -f -d raid1 -m raid1 /dev/sda3 /dev/sdb3

mount /dev/sda3 /mnt

cd /mnt
btrfs subvolume snapshot . __active
btrfs subvolume set-default $(btrfs subvolume list /mnt | awk '{print $2}') .
mkdir __snapshot

cd __active
btrfs subvolume create root
btrfs subvolume create home
btrfs subvolume create var

mkdir /target 
mount -o subvol=__active/root /dev/sda3 /target
mkdir /target/home /target/var
mount -o subvol=__active/home /dev/sda3 /target/home
mount -o subvol=__active/var  /dev/sda3 /target/var

pacstrap /target base base-devel btrfs-progs kexec-tools grub git vim openssh \
  wget

mkdir /target/var/lib/btrfs
mount -o rw,relatime,space_cache,subvolid=0 /dev/sda3 /target/var/lib/btrfs

genfstab -U -p /target >> /target/etc/fstab

cat > /target/run_01.sh <<EOF
#!/bin/bash
set -e
set -o pipefail

git clone https://github.com/xtfxme/mkinitcpio-btrfs
cd mkinitcpio-btrfs
echo Y | makepkg -i
EOF

cat > /target/install.sh <<EOF
#!/bin/bash
set -e
set -o pipefail

sed -i 's/^# %wheel/%wheel/' /etc/sudoers

useradd -m -G wheel doc
echo doc:123123 | chpasswd
su - doc -c /run_01.sh

sed -i 's/fsck)/fsck btrfs)/' /etc/mkinitcpio.conf
mkinitcpio -p linux

grub-install /dev/sda
grub-install /dev/sdb
grub-mkconfig > /boot/grub/grub.cfg

systemctl enable dhcpcd
systemctl enable sshd
EOF

chmod +x /target/run_??.sh
chmod +x /target/install.sh

arch-chroot /target /install.sh

reboot