updated

README.md

@@ -2,7 +2,7 @@
 
 ## Start a NixOS setup with Impermanence
 
-1. Create the configuration with the template
+```txt
     `nix-shell -p git`
     `nix flake new nixos --template git+https://git.krsnik.at/Kristian/impermanence-talk#default --extra-experimental-features "nix-command flakes"`
     `cd nixos`
@@ -10,10 +10,22 @@
     `[CHANGE SETTINGS]`
     `sudo disko --mode disko ./systems/disko.nix`
     `[ENTER PASSWORD FOR ENCRYPTION]`
-    `cd ..`
-    `sudo mv nixos /mnt/persist`
-    `cd nixos /mnt/persist/nixos`
-
     `sudo nixos-generate-config --no-filesystems --force --root /mnt --dir ./system`
     `sudo nixos-install --no-root-password --root /mnt --flake .#default`
 
+    To save the configuration
+    `cd ..`
+    `sudo mv nixos /mnt/persist/etc`
+    `cd /mnt/persist/etc/nixos`
+```
+
+## Get cleared files back
+
+```txt
+cd /tmp
+mkdir mnt
+sudo btrfs subvolume list /
+[NOTE the ID]
+sudo mount /dev/mapper/crypted -o subvolid=[ID] mnt/
+```
+

slides/.~lock.slides.pptx#

@@ -0,0 +1 @@
+,kristian,nixos,09.04.2024 09:22,file:///home/kristian/.config/libreoffice/4;

slides/schema.md

@@ -0,0 +1,69 @@
+```txt
+/nix            /                       /persist
+            +------------------------+
+  /store/x -|-> /var/x               |
+            |   /var/lib/bluetooth <-|-   /var/lib/bluetooth
+  /store/y -|-> /bin/y               |
+            |   /home/admin/.local <-|-   /home/admin/.local
+  /store/z -|-> /etc/z               |
+            +------------------------+
+```
+
+```nix
+{...}: {
+  boot.initrd.postDeviceCommands = lib.mkAfter ''
+    mkdir /btrfs_tmp
+    mount /dev/mapper/crypted /btrfs_tmp
+    if [[ -e /btrfs_tmp/root ]]; then
+        mkdir -p /btrfs_tmp/old_roots
+        timestamp=$(date --date="@$(stat -c %Y /btrfs_tmp/root)" "+%Y-%m-%-d_%H:%M:%S")
+        mv /btrfs_tmp/root "/btrfs_tmp/old_roots/$timestamp"
+    fi
+
+    delete_subvolume_recursively() {
+        IFS=$'\n'
+        for i in $(btrfs subvolume list -o "$1" | cut -f 9- -d ' '); do
+            delete_subvolume_recursively "/btrfs_tmp/$i"
+        done
+        btrfs subvolume delete "$1"
+    }
+
+    for i in $(find /btrfs_tmp/old_roots/ -maxdepth 1 -mtime +30); do
+        delete_subvolume_recursively "$i"
+    done
+
+    btrfs subvolume create /btrfs_tmp/root
+    umount /btrfs_tmp
+  '';
+}
+```
+
+```nix
+{
+  inputs = {
+    impermanence = {
+      url = "github:nix-community/impermanence";
+    };
+  };
+
+  outputs = {self, ...} @ inputs: let
+    system = "x86_64-linux";
+    pkgs = inputs.nixpkgs.legacyPackages.${system};
+  in {
+    nixosConfigurations = {
+      default = inputs.nixpkgs.lib.nixosSystem {
+        inherit system;
+
+        modules = [
+          inputs.impermanence.nixosModules.impermanence
+          ...
+        ];
+      };
+    };
+  }
+}
+```
+
+```txt
+
+```

template/custom/basic.nix

@@ -3,7 +3,7 @@
   lib,
   ...
 }: {
-  networking.hostName = "example";
+  networking.hostName = "nixos";
   networking.firewall.enable = true;
   networking.firewall.allowPing = false;
 
@@ -26,13 +26,16 @@
   users = {
     mutableUsers = false; # Disallow creation of new users and groups
 
-    users."admin" = {
+    users."demo" = {
-      password = "changeme"; # TODO: Maybe put a throw here.
+      password = "demo"; # TODO: Maybe put a throw here.
       isNormalUser = true;
       extraGroups = ["wheel"];
     };
   };
 
+  services.getty.autoLogin = "demo";
+  console.keyMap = "de";
+
   time.timeZone = "Europe/Vienna";
 
   i18n.defaultLocale = "en_US.UTF-8";

template/custom/default.nix

@@ -0,0 +1,5 @@
+{...}: {
+  imports = [
+    ./basic.nix
+  ];
+}

template/flake.nix

@@ -21,20 +21,15 @@
     pkgs = inputs.nixpkgs.legacyPackages.${system};
   in {
     nixosConfigurations = {
-      default = inputs.nixpkgs.lib.nixosSystem {
+      nixos = inputs.nixpkgs.lib.nixosSystem {
         inherit system;
 
         modules = [
           inputs.disko.nixosModules.default
-          # {
-          #   imports = [
-          #     (import ./system/disko.nix {})
-          #   ];
-          # }
-
           inputs.impermanence.nixosModules.impermanence
 
           ./system
+          ./custom
         ];
       };
     };

template/system/default.nix

@@ -4,8 +4,5 @@
     (import ./disko.nix {})
     ./impermanence.nix
     ./configuration.nix
-
-    # Your custom configuration
-    ./custom
   ];
 }

template/system/impermanence.nix

@@ -30,7 +30,7 @@
     directories = [
       {
         directory = "/etc/nixos";
-        user = "admin";
+        user = "demo";
         mode = "u=rwx,g=rx,o=rx";
       }
       "/var/log"
@@ -47,7 +47,7 @@
       }
     ];
 
-    users."admin" = {
+    users."demo" = {
       directories = [
         "this-will-persist"
       ];