Merge pull request #20 from nix-community/updates

hetzner-dedicated updates

hosters/hetzner-dedicated/hetzner-dedicated-wipe-and-install-nixos.sh

@@ -5,7 +5,7 @@
 # This is for a specific server configuration; adjust where needed.
 #
 # Prerequisites:
-#   * Update the script to put in your SSH pubkey, adjust hostname, NixOS version etc.
+#   * Update the script wherever FIXME is present
 #
 # Usage:
 #     ssh root@YOUR_SERVERS_IP bash -s < hetzner-dedicated-wipe-and-install-nixos.sh
@@ -59,9 +59,13 @@ mdadm --stop --scan
 echo 'AUTO -all
 ARRAY <ignore> UUID=00000000:00000000:00000000:00000000' > /etc/mdadm/mdadm.conf
 
+# Create wrapper for parted >= 3.3 that does not exit 1 when it cannot inform
+# the kernel of partitions changing (we use partprobe for that).
+echo -e "#! /usr/bin/env bash\nset -e\n" 'parted $@ 2> parted-stderr.txt || grep "unable to inform the kernel of the change" parted-stderr.txt && echo "This is expected, continuing" || echo >&2 "Parted failed; stderr: $(< parted-stderr.txt)"' > parted-ignoring-partprobe-error.sh && chmod +x parted-ignoring-partprobe-error.sh
+
 # Create partition tables (--script to not ask)
-parted --script /dev/sda mklabel gpt
-parted --script /dev/sdb mklabel gpt
+./parted-ignoring-partprobe-error.sh --script /dev/sda mklabel gpt
+./parted-ignoring-partprobe-error.sh --script /dev/sdb mklabel gpt
 
 # Create partitions (--script to not ask)
 #
@@ -78,10 +82,10 @@ parted --script /dev/sdb mklabel gpt
 #   ... part-type is one of 'primary', 'extended' or 'logical', and may be specified only with 'msdos' or 'dvh' partition tables.
 #   A name must be specified for a 'gpt' partition table.
 # GPT partition names are limited to 36 UTF-16 chars, see https://en.wikipedia.org/wiki/GUID_Partition_Table#Partition_entries_(LBA_2-33).
-parted --script --align optimal /dev/sda -- mklabel gpt mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on mkpart 'data-partition' 2MB '100%'
-parted --script --align optimal /dev/sdb -- mklabel gpt mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on mkpart 'data-partition' 2MB '100%'
+./parted-ignoring-partprobe-error.sh --script --align optimal /dev/sda -- mklabel gpt mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on mkpart 'data-partition' 2MB '100%'
+./parted-ignoring-partprobe-error.sh --script --align optimal /dev/sdb -- mklabel gpt mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on mkpart 'data-partition' 2MB '100%'
 
-# Relaod partitions
+# Reload partitions
 partprobe
 
 # Wait for all devices to exist
@@ -160,8 +164,7 @@ set +u +x # sourcing this may refer to unset variables that we have no control o
 . $HOME/.nix-profile/etc/profile.d/nix.sh
 set -u -x
 
-# Keep in sync with `system.stateVersion` set below!
-# nix-channel --add https://nixos.org/channels/nixos-20.03 nixpkgs
+# FIXME Keep in sync with `system.stateVersion` set below!
 nix-channel --add https://nixos.org/channels/nixos-20.03 nixpkgs
 nix-channel --update
 
@@ -219,7 +222,6 @@ cat > /mnt/etc/nixos/configuration.nix <<EOF
     devices = [ "/dev/sda" "/dev/sdb" ];
   };
 
-
   networking.hostName = "hetzner";
 
   # The mdadm RAID1s were created with 'mdadm --create ... --homehost=hetzner',
@@ -231,13 +233,11 @@ cat > /mnt/etc/nixos/configuration.nix <<EOF
   # This is mdadm's protection against accidentally putting a RAID disk
   # into the wrong machine and corrupting data by accidental sync, see
   # https://bugzilla.redhat.com/show_bug.cgi?id=606481#c14 and onward.
-  # We set the HOMEHOST manually go get the short '/dev/md' names,
-  # and so that things look and are configured the same on all such
-  # machines irrespective of host names.
   # We do not worry about plugging disks into the wrong machine because
-  # we will never exchange disks between machines.
+  # we will never exchange disks between machines, so we tell mdadm to
+  # ignore the homehost entirely.
   environment.etc."mdadm.conf".text = ''
-    HOMEHOST hetzner
+    HOMEHOST <ignore>
   '';
   # The RAIDs are assembled in stage1, so we need to make the config
   # available there.
@@ -248,6 +248,12 @@ cat > /mnt/etc/nixos/configuration.nix <<EOF
   networking.interfaces."$NIXOS_INTERFACE".ipv4.addresses = [
     {
       address = "$IP_V4";
+      # FIXME: The prefix length is commonly, but not always, 24.
+      # You should check what the prefix length is for your server
+      # by inspecting the netmask in the "IPs" tab of the Hetzner UI.
+      # For example, a netmask of 255.255.255.0 means prefix length 24
+      # (24 leading 1s), and 255.255.255.192 means prefix length 26
+      # (26 leading 1s).
       prefixLength = 24;
     }
   ];
@@ -266,12 +272,13 @@ cat > /mnt/etc/nixos/configuration.nix <<EOF
   services.openssh.permitRootLogin = "prohibit-password";
 
   users.users.root.openssh.authorizedKeys.keys = [
-    # Replace this by your SSH pubkey!
+    # FIXME Replace this by your SSH pubkey!
     "ssh-rsa AAAAAAAAAAA..."
   ];
 
   services.openssh.enable = true;
 
+  # FIXME
   # This value determines the NixOS release with which your system is to be
   # compatible, in order to avoid breaking some software such as database
   # servers. You should change this only after NixOS release notes say you

hosters/hetzner-dedicated/zfs-uefi-nvme-nixos.sh

@@ -0,0 +1,417 @@
+#!/usr/bin/env bash
+
+# Installs NixOS on a Hetzner server, wiping the server.
+#
+# This is for a specific server configuration; adjust where needed.
+#
+#
+# Usage:
+#     ssh root@YOUR_SERVERS_IP bash -s < hetzner-dedicated-wipe-and-install-nixos.sh
+#
+# When the script is done, make sure to boot the server from HD, not rescue mode again.
+
+# Explanations:
+#
+# * Following largely https://nixos.org/nixos/manual/index.html#sec-installing-from-other-distro.
+# * and https://nixos.wiki/wiki/NixOS_on_ZFS
+# * **Important:** First you need to boot in legacy-BIOS mode. Then ask for
+# hetzner support to enable UEFI for you.
+# * We set a custom `configuration.nix` so that we can connect to the machine afterwards,
+#   inspired by https://nixos.wiki/wiki/Install_NixOS_on_Hetzner_Online
+# * This server has 2 SSDs.
+#   We put everything on mirror (RAID1 equivalent).
+# * A root user with empty password is created, so that you can just login
+#   as root and press enter when using the Hetzner spider KVM.
+#   Of course that empty-password login isn't exposed to the Internet.
+#   Change the password afterwards to avoid anyone with physical access
+#   being able to login without any authentication.
+# * The script reboots at the end.
+# * exports of env vars are added throughout the script in case you want to run it manually
+export LC_ALL=C
+
+# WARNING: on 2023/07/16 the rescue system of hetzner boots with kernel 6.3.7 which
+# is by default not supported by the latest debian package. You need to update to debian
+# unstable to proceed with the zfs installation.
+
+cat > /etc/apt/preferences.d/90_zfs <<EOF
+Package: libnvpair1linux libnvpair3linux libuutil1linux libuutil3linux libzfs2linux libzfs4linux libzpool2linux libzpool4linux spl-dkms zfs-dkms zfs-test zfsutils-linux zfsutils-linux-dev zfs-zed
+Pin: release n=bullseye-backports
+Pin-Priority: 990
+EOF
+
+apt update -y
+apt install -y dpkg-dev linux-headers-$(uname -r) linux-image-amd64 sudo parted zfs-dkms zfsutils-linux
+
+set -euox pipefail
+
+# hetzner has some weird symlinks to make you install zfs with their script
+rm /usr/local/sbin/zfs || true
+rm /usr/local/sbin/zpool || true
+
+# Inspect existing disks
+# Should give you something like
+# NAME        MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
+# nvme0n1     259:0    0 476.9G  0 disk
+# ├─nvme0n1p1 259:2    0    32G  0 part
+# │ └─md0       9:0    0    32G  0 raid1 [SWAP]
+# ├─nvme0n1p2 259:3    0   512M  0 part
+# │ └─md1       9:1    0   511M  0 raid1 /boot
+# └─nvme0n1p3 259:4    0 444.4G  0 part
+#   └─md2       9:2    0 444.3G  0 raid1 /
+# nvme1n1     259:1    0 476.9G  0 disk
+# ├─nvme1n1p1 259:5    0    32G  0 part
+# │ └─md0       9:0    0    32G  0 raid1 [SWAP]
+# ├─nvme1n1p2 259:6    0   512M  0 part
+# │ └─md1       9:1    0   511M  0 raid1 /boot
+# └─nvme1n1p3 259:7    0 444.4G  0 part
+#   └─md2       9:2    0 444.3G  0 raid1 /
+lsblk
+
+# check the disks that you have available
+# you have to use disks by ID with zfs
+# see https://openzfs.github.io/openzfs-docs/Getting%20Started/Ubuntu/Ubuntu%2020.04%20Root%20on%20ZFS.html#step-2-disk-formatting
+ls /dev/disk/by-id
+# should give you something like this
+# md-name-rescue:0                             nvme-eui.0025388a01051b58-part1
+# md-name-rescue:1                             nvme-eui.0025388a01051b58-part2
+# md-name-rescue:2                             nvme-eui.0025388a01051b58-part3
+# md-uuid-15391820:32e070f6:ecbfb99e:e983e018  nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00424
+# md-uuid-48379d14:3c44fe11:e6528eec:ad784ade  nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00424-part1
+# md-uuid-f2a894fc:9e90e3af:9af81d28:b120ae1f  nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00424-part2
+# nvme-eui.0025388a01051b55                    nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00424-part3
+# nvme-eui.0025388a01051b55-part1              nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00427
+# nvme-eui.0025388a01051b55-part2              nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00427-part1
+# nvme-eui.0025388a01051b55-part3              nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00427-part2
+# nvme-eui.0025388a01051b58                    nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00427-part3
+#
+# we will use the two disks
+# nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00424
+# nvme-SAMSUNG_MZVLB512HBJQ-00000_S4GENA0NA00427
+
+# The following variables should be replaced
+export DISK1=/dev/disk/by-id/nvme-SAMSUNG_MZQLB3T8HALS-00007_S438NC0R804840
+export DISK2=/dev/disk/by-id/nvme-SAMSUNG_MZQLB3T8HALS-00007_S438NC0R811800
+# Replace with your key
+export SSH_PUB_KEY="ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGyQSeQ0CV/qhZPre37+Nd0E9eW+soGs+up6a/bwggoP raphael@RAPHAELs-MacBook-Pro.local"
+# choose whatever you want, it doesn't matter
+export MY_HOSTNAME=htz
+# this has to be a number in this format exactly. You can replace the numbers though
+export MY_HOSTID=00000001
+
+# Undo existing setups to allow running the script multiple times to iterate on it.
+# We allow these operations to fail for the case the script runs the first time.
+umount /mnt || true
+vgchange -an || true
+
+# Stop all mdadm arrays that the boot may have activated.
+mdadm --stop --scan
+
+# Prevent mdadm from auto-assembling arrays.
+# Otherwise, as soon as we create the partition tables below, it will try to
+# re-assemple a previous RAID if any remaining RAID signatures are present,
+# before we even get the chance to wipe them.
+# From:
+#     https://unix.stackexchange.com/questions/166688/prevent-debian-from-auto-assembling-raid-at-boot/504035#504035
+# We use `>` because the file may already contain some detected RAID arrays,
+# which would take precedence over our `<ignore>`.
+echo 'AUTO -all
+ARRAY <ignore> UUID=00000000:00000000:00000000:00000000' > /etc/mdadm/mdadm.conf
+
+# Create wrapper for parted >= 3.3 that does not exit 1 when it cannot inform
+# the kernel of partitions changing (we use partprobe for that).
+echo -e "#! /usr/bin/env bash\nset -e\n" 'parted $@ 2> parted-stderr.txt || grep "unable to inform the kernel of the change" parted-stderr.txt && echo "This is expected, continuing" || echo >&2 "Parted failed; stderr: $(< parted-stderr.txt)"' > parted-ignoring-partprobe-error.sh && chmod +x parted-ignoring-partprobe-error.sh
+
+# Create partition tables (--script to not ask)
+./parted-ignoring-partprobe-error.sh --script $DISK1 mklabel gpt
+./parted-ignoring-partprobe-error.sh --script $DISK2 mklabel gpt
+
+# Create partitions (--script to not ask)
+#
+# We create the 1MB BIOS boot partition at the front.
+#
+# Note we use "MB" instead of "MiB" because otherwise `--align optimal` has no effect;
+# as per documentation https://www.gnu.org/software/parted/manual/html_node/unit.html#unit:
+# > Note that as of parted-2.4, when you specify start and/or end values using IEC
+# > binary units like "MiB", "GiB", "TiB", etc., parted treats those values as exact
+#
+# Note: When using `mkpart` on GPT, as per
+#   https://www.gnu.org/software/parted/manual/html_node/mkpart.html#mkpart
+# the first argument to `mkpart` is not a `part-type`, but the GPT partition name:
+#   ... part-type is one of 'primary', 'extended' or 'logical', and may be specified only with 'msdos' or 'dvh' partition tables.
+#   A name must be specified for a 'gpt' partition table.
+# GPT partition names are limited to 36 UTF-16 chars, see https://en.wikipedia.org/wiki/GUID_Partition_Table#Partition_entries_(LBA_2-33).
+# TODO the bios partition should not be this big
+# however if it's less the installation fails with
+# cannot copy /nix/store/d4xbrrailkn179cdp90v4m57mqd73hvh-linux-5.4.100/bzImage to /boot/kernels/d4xbrrailkn179cdp90v4m57mqd73hvh-linux-5.4.100-bzImage.tmp: No space left on device
+./parted-ignoring-partprobe-error.sh --script --align optimal $DISK1 -- mklabel gpt \
+    mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on \
+    mkpart 'EFI-system-partition' 2MB 512MB set 2 esp on \
+    mkpart 'data-partition' 512MB '100%'
+
+./parted-ignoring-partprobe-error.sh --script --align optimal $DISK2 -- mklabel gpt \
+    mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on \
+    mkpart 'EFI-system-partition' 2MB 512MB set 2 esp on \
+    mkpart 'data-partition' 512MB '100%'
+
+# Reload partitions
+partprobe
+
+# Wait for all devices to exist
+udevadm settle --timeout=5 --exit-if-exists=$DISK1-part1
+udevadm settle --timeout=5 --exit-if-exists=$DISK1-part2
+udevadm settle --timeout=5 --exit-if-exists=$DISK1-part3
+udevadm settle --timeout=5 --exit-if-exists=$DISK2-part1
+udevadm settle --timeout=5 --exit-if-exists=$DISK2-part2
+udevadm settle --timeout=5 --exit-if-exists=$DISK2-part3
+
+# Wipe any previous RAID signatures
+# sometimes they are not on a specific disk for some reason
+mdadm --zero-superblock --force $DISK1-part1 || true
+mdadm --zero-superblock --force $DISK1-part2 || true
+mdadm --zero-superblock --force $DISK1-part3 || true
+mdadm --zero-superblock --force $DISK2-part1 || true
+mdadm --zero-superblock --force $DISK2-part2 || true
+mdadm --zero-superblock --force $DISK2-part3 || true
+
+# Creating file systems changes their UUIDs.
+# Trigger udev so that the entries in /dev/disk/by-uuid get refreshed.
+# `nixos-generate-config` depends on those being up-to-date.
+# See https://github.com/NixOS/nixpkgs/issues/62444
+udevadm trigger
+
+# taken from https://nixos.wiki/wiki/NixOS_on_ZFS
+# somehow there is a weird symlink in the default zfs
+zpool create -O mountpoint=none \
+    -O atime=off \
+    -O compression=lz4 \
+    -O xattr=sa \
+    -O acltype=posixacl \
+    -o ashift=12 \
+    -f \
+    root_pool mirror $DISK1-part3 $DISK2-part3
+
+# Create the filesystems. This layout is designed so that /home is separate from the root
+# filesystem, as you'll likely want to snapshot it differently for backup purposes. It also
+# makes a "nixos" filesystem underneath the root, to support installing multiple OSes if
+# that's something you choose to do in future.
+zfs create -o mountpoint=legacy root_pool/root
+zfs create -o mountpoint=legacy root_pool/root/nixos
+zfs create -o mountpoint=legacy root_pool/home
+# add 1G of reseved space in case the disk gets full
+# zfs needs space to delete files
+zfs create -o refreservation=1G -o mountpoint=none root_pool/reserved
+# this creates a special volume for db data see https://wiki.archlinux.org/index.php/ZFS#Databases
+zfs create -o mountpoint=legacy \
+    -o recordsize=8K \
+    -o primarycache=metadata \
+    -o logbias=throughput \
+    root_pool/postgres
+
+# NixOS pre-installation mounts
+#
+# Mount the filesystems manually. The nixos installer will detect these mountpoints
+# and save them to /mnt/nixos/hardware-configuration.nix during the install process.
+mount -t zfs root_pool/root/nixos /mnt
+mkdir /mnt/home
+mount -t zfs root_pool/home /mnt/home
+mkdir -p /mnt/var/lib/postgres
+mount -t zfs root_pool/postgres /mnt/var/lib/postgres
+
+# Create a raid mirror for the efi boot
+# see https://docs.hetzner.com/robot/dedicated-server/operating-systems/efi-system-partition/
+# TODO check this though the following article says it doesn't work properly
+# https://outflux.net/blog/archives/2018/04/19/uefi-booting-and-raid1/ 
+mdadm --create --run --verbose /dev/md127 \
+    --level 1 \
+    --raid-disks 2 \
+    --metadata 1.0 \
+    --homehost=$MY_HOSTNAME \
+    --name=boot_efi \
+    $DISK1-part2 $DISK2-part2
+
+# Assembling the RAID can result in auto-activation of previously-existing LVM
+# groups, preventing the RAID block device wiping below with
+# `Device or resource busy`. So disable all VGs first.
+vgchange -an
+
+# Wipe filesystem signatures that might be on the RAID from some
+# possibly existing older use of the disks (RAID creation does not do that).
+# See https://serverfault.com/questions/911370/why-does-mdadm-zero-superblock-preserve-file-system-information
+wipefs -a /dev/md127
+
+# Disable RAID recovery. We don't want this to slow down machine provisioning
+# in the rescue mode. It can run in normal operation after reboot.
+echo 0 > /proc/sys/dev/raid/speed_limit_max
+
+# Filesystems (-F to not ask on preexisting FS)
+mkfs.vfat -F 32 /dev/md127
+
+# Creating file systems changes their UUIDs.
+# Trigger udev so that the entries in /dev/disk/by-uuid get refreshed.
+# `nixos-generate-config` depends on those being up-to-date.
+# See https://github.com/NixOS/nixpkgs/issues/62444
+udevadm trigger
+
+mkdir -p /mnt/boot/efi
+mount /dev/md127 /mnt/boot/efi
+
+# Installing nix
+
+# Allow installing nix as root, see
+#   https://github.com/NixOS/nix/issues/936#issuecomment-475795730
+mkdir -p /etc/nix
+echo "build-users-group =" > /etc/nix/nix.conf
+
+# using determinate systems installer, for more information
+# check https://github.com/DeterminateSystems/nix-installer
+curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix | sh -s -- install
+
+# Keep in sync with `system.stateVersion` set below!
+nix-channel --add https://nixos.org/channels/nixos-23.05 nixpkgs
+nix-channel --update
+
+# TODO use something like nix shell nixpkgs#nixos-generate-config nixpkgs#nixos-install nixpkgs#nixos-enter nixpkgs#manual.manpages
+# Getting NixOS installation tools
+nix-env -iE "_: with import <nixpkgs/nixos> { configuration = {}; }; with config.system.build; [ nixos-generate-config nixos-install nixos-enter manual.manpages ]"
+
+# TODO
+# perl: warning: Please check that your locale settings:
+#         LANGUAGE = (unset),
+#         LC_ALL = "en_US.UTF-8",
+#         LANG = "en_US.UTF-8"
+#     are supported and installed on your system.
+nixos-generate-config --root /mnt
+
+# Find the name of the network interface that connects us to the Internet.
+# Inspired by https://unix.stackexchange.com/questions/14961/how-to-find-out-which-interface-am-i-using-for-connecting-to-the-internet/302613#302613
+export RESCUE_INTERFACE=$(ip route get 8.8.8.8 | grep -Po '(?<=dev )(\S+)')
+# Find what its name will be under NixOS, which uses stable interface names.
+# See https://major.io/2015/08/21/understanding-systemds-predictable-network-device-names/#comment-545626
+# NICs for most Hetzner servers are not onboard, which is why we use
+# `ID_NET_NAME_PATH`otherwise it would be `ID_NET_NAME_ONBOARD`.
+export INTERFACE_DEVICE_PATH=$(udevadm info -e | grep -Po "(?<=^P: )(.*${RESCUE_INTERFACE})")
+export UDEVADM_PROPERTIES_FOR_INTERFACE=$(udevadm info --query=property "--path=$INTERFACE_DEVICE_PATH")
+export NIXOS_INTERFACE=$(echo "$UDEVADM_PROPERTIES_FOR_INTERFACE" | grep -o -E 'ID_NET_NAME_PATH=\w+' | cut -d= -f2)
+echo "Determined NIXOS_INTERFACE as '$NIXOS_INTERFACE'"
+export IP_V4=$(ip route get 8.8.8.8 | grep -Po '(?<=src )(\S+)')
+echo "Determined IP_V4 as $IP_V4"
+# Find what its name will be under NixOS, which uses stable interface names.
+# See https://major.io/2015/08/21/understanding-systemds-predictable-network-device-names/#comment-545626
+# NICs for most Hetzner servers are not onboard, which is why we use
+# `ID_NET_NAME_PATH`otherwise it would be `ID_NET_NAME_ONBOARD`.
+export INTERFACE_DEVICE_PATH=$(udevadm info -e | grep -Po "(?<=^P: )(.*${RESCUE_INTERFACE})")
+export UDEVADM_PROPERTIES_FOR_INTERFACE=$(udevadm info --query=property "--path=$INTERFACE_DEVICE_PATH")
+export NIXOS_INTERFACE=$(echo "$UDEVADM_PROPERTIES_FOR_INTERFACE" | grep -o -E 'ID_NET_NAME_PATH=\w+' | cut -d= -f2)
+echo "Determined NIXOS_INTERFACE as '$NIXOS_INTERFACE'"
+
+# Determine Internet IPv6 by checking route, and using ::1
+# (because Hetzner rescue mode uses ::2 by default).
+# The `ip -6 route get` output on Hetzner looks like:
+#   # ip -6 route get 2001:4860:4860:0:0:0:0:8888
+#   2001:4860:4860::8888 via fe80::1 dev eth0 src 2a01:4f8:151:62aa::2 metric 1024  pref medium
+export IP_V6="$(ip route get 2001:4860:4860::8888 | head -1 | cut -d' ' -f7 | cut -d: -f1-4)::1"
+echo "Determined IP_V6 as $IP_V6"
+
+# From https://stackoverflow.com/questions/1204629/how-do-i-get-the-default-gateway-in-linux-given-the-destination/15973156#15973156
+read _ _ DEFAULT_GATEWAY _ < <(ip route list match 0/0); echo "$DEFAULT_GATEWAY"
+echo "Determined DEFAULT_GATEWAY as $DEFAULT_GATEWAY"
+
+# Generate `configuration.nix`. Note that we splice in shell variables.
+cat > /mnt/etc/nixos/configuration.nix <<EOF
+{ config, pkgs, ... }:
+
+{
+  imports =
+    [ # Include the results of the hardware scan.
+      ./hardware-configuration.nix
+    ];
+
+  # Use GRUB2 as the boot loader.
+  # We don't use systemd-boot because Hetzner uses BIOS legacy boot.
+  boot.loader.systemd-boot.enable = false;
+  boot.loader.grub = {
+    enable = true;
+    efiSupport = false;
+    devices = ["$DISK1" "$DISK2"];
+    copyKernels = true; 
+  };
+  boot.supportedFilesystems = [ "zfs" ];
+
+  networking.hostName = "$MY_HOSTNAME";
+  networking.hostId = "$MY_HOSTID";
+  
+  # enable flakes by default
+  nix = {
+    package = pkgs.nixFlakes;
+    extraOptions = ''
+      experimental-features = nix-command flakes
+    '';
+  };
+
+  # Set your time zone.
+  time.timeZone = "Etc/UTC";
+
+  environment = {
+    enableDebugInfo = true;
+    # just a couple of packages to make our lives easier
+    systemPackages = with pkgs; [ vim ];
+  };
+
+  # Network (Hetzner uses static IP assignments, and we don't use DHCP here)
+  networking.useDHCP = false;
+  networking.interfaces."$NIXOS_INTERFACE".ipv4.addresses = [
+    {
+      address = "$IP_V4";
+      prefixLength = 24;
+    }
+  ];
+  networking.interfaces."$NIXOS_INTERFACE".ipv6.addresses = [
+    {
+      address = "$IP_V6";
+      prefixLength = 64;
+    }
+  ];
+  networking.defaultGateway = "$DEFAULT_GATEWAY";
+  networking.defaultGateway6 = { address = "fe80::1"; interface = "$NIXOS_INTERFACE"; };
+  networking.nameservers = [
+    # cloudflare
+    "1.1.1.1"
+    "2606:4700:4700::1111"
+    "2606:4700:4700::1001"
+    # google
+    "8.8.8.8"
+    "2001:4860:4860::8888"
+    "2001:4860:4860::8844"
+  ];
+
+  # Initial empty root password for easy login:
+  users.users.root.initialHashedPassword = "";
+  services.openssh.permitRootLogin = "prohibit-password";
+
+  users.users.root.openssh.authorizedKeys.keys = ["$SSH_PUB_KEY"];
+
+  services.openssh.enable = true;
+
+  # This value determines the NixOS release with which your system is to be
+  # compatible, in order to avoid breaking some software such as database
+  # servers. You should change this only after NixOS release notes say you
+  # should.
+  system.stateVersion = "23.05"; # Did you read the comment?
+}
+EOF
+
+# Install NixOS
+PATH="$PATH" $(which nixos-install) \
+  --no-root-passwd --root /mnt --max-jobs 40
+
+umount /mnt
+
+reboot
+
+# if you need to debug something
+# - connect to the rescue system
+# - install zfs
+# ```
+# zpool import -f root_pool temp_pool
+# mount -t zfs temp_pool/root/nixos /mnt
+# journalctl --directory=/mnt/var/log/journal

hosters/leaseweb-dedicated/leaseweb-dedicated-wipe-and-install-nixos.sh

@@ -61,9 +61,13 @@ mdadm --stop --scan
 echo 'AUTO -all
 ARRAY <ignore> UUID=00000000:00000000:00000000:00000000' > /etc/mdadm/mdadm.conf
 
+# Create wrapper for parted >= 3.3 that does not exit 1 when it cannot inform
+# the kernel of partitions changing (we use partprobe for that).
+echo -e "#! /usr/bin/env bash\nset -e\n" 'parted $@ 2> parted-stderr.txt || grep "unable to inform the kernel of the change" parted-stderr.txt && echo "This is expected, continuing" || echo >&2 "Parted failed; stderr: $(< parted-stderr.txt)"' > parted-ignoring-partprobe-error.sh && chmod +x parted-ignoring-partprobe-error.sh
+
 # Create partition tables (--script to not ask)
-parted --script /dev/sda mklabel gpt
-parted --script /dev/sdb mklabel gpt
+./parted-ignoring-partprobe-error.sh /dev/sda mklabel gpt
+./parted-ignoring-partprobe-error.sh /dev/sdb mklabel gpt
 
 # Create partitions (--script to not ask)
 #
@@ -80,8 +84,8 @@ parted --script /dev/sdb mklabel gpt
 #   ... part-type is one of 'primary', 'extended' or 'logical', and may be specified only with 'msdos' or 'dvh' partition tables.
 #   A name must be specified for a 'gpt' partition table.
 # GPT partition names are limited to 36 UTF-16 chars, see https://en.wikipedia.org/wiki/GUID_Partition_Table#Partition_entries_(LBA_2-33).
-parted --script --align optimal /dev/sda -- mklabel gpt mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on mkpart 'data-partition' 2MB '100%'
-parted --script --align optimal /dev/sdb -- mklabel gpt mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on mkpart 'data-partition' 2MB '100%'
+./parted-ignoring-partprobe-error.sh --align optimal /dev/sda -- mklabel gpt mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on mkpart 'data-partition' 2MB '100%'
+./parted-ignoring-partprobe-error.sh --align optimal /dev/sdb -- mklabel gpt mkpart 'BIOS-boot-partition' 1MB 2MB set 1 bios_grub on mkpart 'data-partition' 2MB '100%'
 
 # Relaod partitions
 partprobe

hosters/ovh-dedicated/ovh-dedicated-wipe-and-install-nixos.sh

@@ -57,12 +57,16 @@ set -e
 # Stop all mdadm arrays that the boot may have activated.
 mdadm --stop --scan
 
+# Create wrapper for parted >= 3.3 that does not exit 1 when it cannot inform
+# the kernel of partitions changing (we use partprobe for that).
+echo -e "#! /usr/bin/env bash\nset -e\n" 'parted $@ 2> parted-stderr.txt || grep "unable to inform the kernel of the change" parted-stderr.txt && echo "This is expected, continuing" || echo >&2 "Parted failed; stderr: $(< parted-stderr.txt)"' > parted-ignoring-partprobe-error.sh && chmod +x parted-ignoring-partprobe-error.sh
+
 # Create partition tables (--script to not ask)
-parted --script /dev/sda mklabel gpt
-parted --script /dev/sdb mklabel gpt
-parted --script /dev/sdc mklabel gpt
-parted --script /dev/sdd mklabel gpt
-parted --script /dev/nvme0n1 mklabel gpt
+./parted-ignoring-partprobe-error.sh --script /dev/sda mklabel gpt
+./parted-ignoring-partprobe-error.sh --script /dev/sdb mklabel gpt
+./parted-ignoring-partprobe-error.sh --script /dev/sdc mklabel gpt
+./parted-ignoring-partprobe-error.sh --script /dev/sdd mklabel gpt
+./parted-ignoring-partprobe-error.sh --script /dev/nvme0n1 mklabel gpt
 
 # Create partitions (--script to not ask)
 #
@@ -84,10 +88,10 @@ parted --script /dev/nvme0n1 mklabel gpt
 #   ... part-type is one of 'primary', 'extended' or 'logical', and may be specified only with 'msdos' or 'dvh' partition tables.
 #   A name must be specified for a 'gpt' partition table.
 # GPT partition names are limited to 36 UTF-16 chars, see https://en.wikipedia.org/wiki/GUID_Partition_Table#Partition_entries_(LBA_2-33).
-parted --script --align optimal /dev/sda -- mklabel gpt mkpart 'ESP-partition0'        fat32 1MB 551MB set 1 esp on  mkpart 'OS-partition0' 551MB 500GB mkpart 'data-partition0' 500GB '100%'
-parted --script --align optimal /dev/sdb -- mklabel gpt mkpart 'ESP-partition1'        fat32 1MB 551MB set 1 esp on  mkpart 'OS-partition1' 551MB 500GB mkpart 'data-partition1' 500GB '100%'
-parted --script --align optimal /dev/sdc -- mklabel gpt mkpart 'ESP-partition2-unused' fat32 1MB 551MB set 1 esp off                                    mkpart 'data-partition2' 551MB '100%'
-parted --script --align optimal /dev/sdd -- mklabel gpt mkpart 'ESP-partition3-unused' fat32 1MB 551MB set 1 esp off                                    mkpart 'data-partition3' 551MB '100%'
+./parted-ignoring-partprobe-error.sh --script --align optimal /dev/sda -- mklabel gpt mkpart 'ESP-partition0'        fat32 1MB 551MB set 1 esp on  mkpart 'OS-partition0' 551MB 500GB mkpart 'data-partition0' 500GB '100%'
+./parted-ignoring-partprobe-error.sh --script --align optimal /dev/sdb -- mklabel gpt mkpart 'ESP-partition1'        fat32 1MB 551MB set 1 esp on  mkpart 'OS-partition1' 551MB 500GB mkpart 'data-partition1' 500GB '100%'
+./parted-ignoring-partprobe-error.sh --script --align optimal /dev/sdc -- mklabel gpt mkpart 'ESP-partition2-unused' fat32 1MB 551MB set 1 esp off                                    mkpart 'data-partition2' 551MB '100%'
+./parted-ignoring-partprobe-error.sh --script --align optimal /dev/sdd -- mklabel gpt mkpart 'ESP-partition3-unused' fat32 1MB 551MB set 1 esp off                                    mkpart 'data-partition3' 551MB '100%'
 
 # Relaod partitions
 partprobe