# Install NixOS on OCI

# The hostname of the to-be-installed machine.
# It's used to select the configuration.
name=example

# The IP address or domain name of the to-be-installed machine.
target=INSERT_YOUR_PUBLIC_IP_HERE

# The machine hardware name of the target machine.
# Supported values: aarch64, x86_64
machine=aarch64

kexec_tarball=$(nix-build --no-out-link '<nixpkgs/nixos>' -A config.system.build.kexec_tarball -I nixos-config=./kexec.nix)
scp $kexec_tarball/tarball/nixos-system-$machine-linux.tar.xz ubuntu@$target:/tmp/

ssh ubuntu@$target sudo tar -C / -xf /tmp/nixos-system-$machine-linux.tar.xz
ssh ubuntu@$target sudo /kexec_nixos

sed -i "/^$target /d" ~/.ssh/known_hosts
ssh root@$target

# If the VM doesn't have enough memory, add a swap device and
# increase the size of the kexec's Nix store.
if test "$(free -m | awk '/^Mem:/{print$2}')" -lt 1024; then
  printf '%s\n' label:gpt ,512M,U ,4G,S ,,L | sfdisk /dev/sda
  mkfs.fat -F 32 -n boot /dev/sda1
  mkswap -L swap /dev/sda2
  mkfs.ext4 -L root /dev/sda3
  swapon /dev/disk/by-label/swap
  mount -o remount,size=800M /nix/.rw-store/
else
  printf '%s\n' label:gpt ,512M,U ,,L | sfdisk /dev/sda
  mkfs.fat -F 32 -n boot /dev/sda1
  mkfs.ext4 -L root /dev/sda2
fi

mkdir -m 0000 -p /mnt && mount /dev/disk/by-label/root /mnt
mkdir -m 0000 -p /mnt/boot && mount /dev/disk/by-label/boot /mnt/boot

nix-channel --add https://nixos.org/channels/nixos-23.05 nixpkgs
nix-channel --update

ssh root@$target mkdir -p /mnt/etc/nixos

rsync -va "$name"/ root@$target:/mnt/etc/nixos/

nixos-install --no-root-passwd
shutdown -r now

sed -i "/^$target /d" ~/.ssh/known_hosts
ssh root@$target