nixfiles

Bootstrap a new NixOS machine

NixOS can be bootstrapped onto new machines from a live disk. This method requires minimal user input, and allows NixOS to be installed from existing configuration.

Create a Nix live disk

1. Download the (minimal) Nix ISO, see Download.
2. Plugin the flash drive and unmount if needed.
3. Write the ISO to the flash drive.

   sudo dd if=<path to .iso> of=/dev/sd<drive letter> bs=4M status=progress oflag=sync

4. Boot into the flash drive and select NixOS ... Installer.

Prepare the live disk environment

The minimal Nix ISO does not have network manager, so WIFI is configured manually.

1. Configure the WIFI credentials.xsel

   wpa_passphrase <WIFI SSID> > wifi.conf

2. Get the name of the WIFI interface.

   ls /sys/class/net | grep w

3. Connect to the WIFI endpoint.

   sudo wpa_supplicant -i <WIFI interface> -c wifi.conf -B

Install NixOS

1. Clone the Nix configuration.

   git clone https://github.com/eric-carlsson/nixfiles.git
   cd nixfiles

2. Before proceeding, the NixOS configuration should contain hardware and disk configuration files. Hardware configuration can be generated (without filesystem config since this is managed by disko).

   sudo nixos-generate-config --no-filesystems --show-hardware-config

3. Format disk(s).

   sudo nix --experimental-features "nix-command flakes" run github:nix-community/disko/latest -- --mode destroy,format,mount --flake .#<hostname>

4. Install NixOS.

   sudo nixos-install --no-root-passwd --flake .#<hostname>

5. Set the user login password.

   sudo nixos-enter --root /mnt -c 'passwd <username>'

6. Reboot.

WIP: Single cmd install with disko-install

Prepare the live disk environment

The minimal Nix installer uses an in-memory file system for the Nix store. This tends cause OOM issues. Solve this by creating a swap partition.

1. Create a new partition.

   sudo fdisk /dev/sd<drive letter>

   Enter n and press enter until asked to enter the last sector. Enter a size that will fit on the flash drive, for example +16000M. Once created, assign a type by entering t and entering 82. Enter w to write changes to disk.
2. Format the swap partition.

   sudo mkswap /dev/sd<drive letter><partition number>

3. Activate the swap partition.

   sudo swapon /dev/sd<drive letter><partition number>

4. Remount the Nix store to use the swap space.

   sudo mount -o remount,size=15G,noatime /nix/.rw-store

Generate hardware configuration

Generate a hardware configuration file for the machine.

sudo nixos-generate-config --no-filesystems --show-hardware-config

Add the output to host/<hostname>/hardware-configuration.nix and push to remote.

Install NixOS

sudo nix \
    --extra-experimental-features 'flakes nix-command' \
    run github:nix-community/disko#disko-install -- \
    --flake "github:eric-carlsson/nixfiles#<hostname>" \
    --write-efi-boot-entries \
    --disk main "<disk device>"