build.sh

#!/bin/sh

set -eux

export TARGET="$1"
export NIX_PATH=nixpkgs="https://github.com/NixOS/nixpkgs-channels/archive/nixos-unstable.tar.gz"
export _SSH="ssh -o UserKnownHostsFile=./kn root@${TARGET}"
echo "" > kn

nix-build \
    '<nixpkgs/nixos>' \
    -A config.system.build.kexec_tarball \
    -I nixos-config=./configuration.nix\
    -Q -j 4

while ! [ x`$_SSH "/bin/bash -c 'echo foo'"` = "xfoo" ]; do
    sleep 1
done


rsync result/tarball/nixos-system-x86_64-linux.tar.xz \
      -e 'ssh -o UserKnownHostsFile=./kn ' \
      root@${TARGET}:~/

$_SSH '/bin/bash -c \
    "tar -C / -xf /root/nixos-system-*.tar.xz; /kexec_nixos"' &


# Wait for it to go down
while [ x`$_SSH "/bin/sh -c 'echo foo'"` = "xfoo" ]; do
    sleep 1
done


echo "" > kn

sleep 5

while ! [ x`$_SSH "/bin/sh -c 'echo foo'"` = "xfoo" ]; do
    sleep 1
done


scp -o UserKnownHostsFile=./kn run.sh root@${TARGET}:~/run.sh
$_SSH "/bin/bash -c 'chmod +x run.sh; ./run.sh'"

run.sh

#!/bin/sh

extracfg() {
    cat <<EOF
{
  boot.loader.grub.devices = [ "/dev/sda" "/dev/sdb" ];
  services.openssh.enable = true;
  users.users.root.openssh.authorizedKeys.keys = [ "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDa8JEOIubMB6khJYaY2q7fpco+q5RCo5HHwdUrngR4kGCXvdeou0tNldMrR0mshIDBJ4VoI0rTFUe3Sb8W+7iknxHSsY6+7fzQ2DvW7JYmtprEJrlOheqKWzjtLgR1hERDugM1LvFGUUpUj5mZpC2yzJnOuc/jlZ1KWjcK44YyJveqxo128Kv3Xqiz85Bt+nAD69cDs8LzOzvH6YI7RcPmzo04h01eJqcGY3lbOmbfJFvJyB8RhJx7phIALmo3BWITKcc00Hyw52tu86WzMPQuSEn5e9Fel6SL/sdLpxT4V9e8v64TrsNPQrGEw+C2MRYHLE5gqKDLMy/ZK8dA5TMF gchristensen@Lrr.local" ];
}
EOF

}

# partition

mdadm --stop /dev/md12{6,7}
mdadm --create --verbose /dev/md0 --level=0 --raid-devices=4 /dev/sd{c,d,e,f}
mkfs.ext4 /dev/md0

nixos-generate-config --root /mnt
sed -i "s#./hardware-configuration.nix#./hardware-configuration.nix ./extra.nix#" /mnt/etc/nixos/configuration.nix

extracfg > /mnt/etc/nixos/extra.nix

nixos-install