nixos-conf/README.md

NixOS Configuration Files wit Flakes, Home-Manager

Description

My NixOS configuration repository

Install a New Host

1. Install NixOS with graphical ISO image (e.g. GNOME). During the installation the desktop environment can be choosen.
2. Reboot into NixOS
3. Edit /etc/nixos/configuration.nix with sudoedit
   • Change hostname
   • Enable flakes by adding the line nix.settings.experimental-features = [ "nix-command" "flakes" ];
   • Install tmux, neovim, git by adding them to environment.systemPackages = with pkgs; [
4. Apply changes: sudo nixos-rebuild switch and reboot
5. Clone NixOS config repository to /home/$USER/nixos:

cd $HOME
git clone https://git.plueschbit.de/jan/nixos-conf ~/nixos

6. Add the new host to repository
   • Create ~/nixos/hosts/$HOSTNAME
   • cp /etc/nixos/*.nix $HOSTNAME/.
   • Edit ~/nixos/flake.nix and add section for new host
   • Stage new config files: git add flake.nix hosts/$HOSTNAME/*. Otherwise, nixos-rebuild will refuse to work with the files.
7. Apply config: sudo nixos-rebuild switch --flake ~/nixos/#<host>

Update Packages on a Host

Update of the file flake.nix:

cd ~/nixos
sudo nix flake update

Then, perform nixos rebuild:

sudo nixos-rebuild switch --flake ~/nixos/#<host>

Upgrading to a new NixOS channel

List the current channels:

sudo nix-channel --list

Change the channel nixos:

sudo nix-channel --add https://nixos.org/channels/nixos-<rel>

Then, perform an update like above.

Garbage Collection

List all generations:

sudo nix-env --list-generations --profile /nix/var/nix/profiles/system

Keep e.g. the last five generations and perform garbage collection:

sudo nix-env --delete-generations +5 --profile /nix/var/nix/profiles/system
sudo nix-collect-garbage