nix-config

Configuration files for my NixOS machines and home configurations.

Machine setup - for NixOS

1. Clone this repo into the home directory of a NixOS-system and change into it.
2. Run the following command when initially setting up the system:

   sudo nixos-rebuild switch --flake .#<<machine>>

3. If there is a justfile defined by the machine's user, it will be automatically created in the nix-config directory. It leverages just to define simple commands for doing NixOS housekeeping, like switching configurations and updating the system.

Home Manager setup - for non-NixOS

1. Clone this repo into the home directory of a NixOS-system and change into it.
2. Run the following command when initially setting up Home Manager:

   nix run nixpkgs#home-manager -- switch --flake .#<<home config>> # --impure could be necessary

3. If there is a justfile defined by the user, it will be automatically created in the nix-config directory. It leverages just to define simple commands for doing Home Manager housekeeping, like switching configurations and updating the setup.

Project structure

lib

Utilities and helper functions.

machines

Configurations and hardware configurations specific to the respective machine. Each machine config also contains the respective Home Manager user config, if defined.

modules/nixos

NixOS modules.

modules/home-manager

Home Manger modules.

home

Home Manager configurations for a standalone user config.

overlays

Package overlays.

Bootstrapping machines

orville

Note: The config sets a static IPv4 address and other network options. Check that the IP address is not already in used in your network. For step 4 you will need to use this IP address.

1. Run a graphical NixOS-installer image (the permissions/authentication can be a problem on the minimal ISOs).
2. Set a password for the nixos user via passwd.
3. Run the following command from the root of this repository and use the just created password when promted. Note: If there is already an existing hardware-configuration.nix, you don't need the corresponding options.

   nix run github:nix-community/nixos-anywhere -- \
     --flake .#orville \
     --build-on-remote \
     --generate-hardware-config \
     nixos-generate-config \
     machines/orville/hardware-configuration.nix \
     --target-host nixos@<IP address of the remote host>

4. The setup is complete. To apply changes in the future, run the following command.

   NIX_SSHOPTS="-i /home/steve/.ssh/id_orville_ed25519" nixos-rebuild switch \
     --flake .#orville \
     --target-host steve@<IP address of the remote host>
     --sudo --ask-sudo-password

discovery

Note: The config sets a static IPv4 address and other network options. Check that the IP address is not already in used in your network. For step 4 you will need to use this IP address.

1. Build the SD card image: nix build .#packages.aarch64-linux.discovery-sdcard-image
   • You need to be capable of building for aarch64-linux, either by
     • building on a native aarch64-linux host,
     • building on a remote aarch64-linux machine, or
     • by having aarch64-linux emulation enabled on your build machine, typically via

       boot.binfmt.emulatedSystems = [ "aarch64-linux" ];

   • The built image file will be ./result/sd-image/nixos-discovery-sdcard-aarch64-linux.img
   • It contains the whole final system and is not an installer. Because we can just flash the complete system image onto the SD card, there is no need for an installer.
2. Flash the image onto the SD card:
   IMPORTANT: dd will destroy your data! Triple check that you selected the right output device!!!
   Select your target device being flashed via lsblk -f, then replace the desired device (e.g. /dev/sdb) in the following command:

   sudo dd if=./result/sd-image/nixos-discovery-sdcard-aarch64-linux.img of=/dev/null bs=4096 conv=fsync status=progress

   This may take some minutes. Don't cancel the command!
3. Insert the SD card into the device and boot.
4. The setup is complete. To apply changes in the future, run the following command.

   NIX_SSHOPTS="-i /home/steve/.ssh/id_discovery_ed25519" \
     nixos-rebuild switch \
     --flake .#discovery \
     --target-host steve@<IP address of the remote host>
     --sudo --ask-sudo-password