nix: add sanoid module + enable on loki,t14

nix/hosts/loki/configuration.nix

@@ -21,6 +21,7 @@
 
     ../../modules/base.nix
     ../../modules/dnscrypt.nix
+    ../../modules/sanoid.nix
     ../../modules/uptime-kuma.nix
     ../../modules/zram.nix
   ];
@@ -195,6 +196,39 @@
       ];
     };
 
+    sanoid = {
+      enable = true;
+      interval = "*:0/5";
+      datasets = {
+        "zroot/DATA/services/nextcloud" = {
+          useTemplate = ["frequent"];
+          recursive = "zfs";
+        };
+        "zroot/DATA/services/gonic" = {
+          useTemplate = ["production"];
+          recursive = "zfs";
+        };
+        "zroot/DATA/services/attic" = {
+          useTemplate = ["production"];
+          recursive = "zfs";
+        };
+        "zroot/DATA/services/uptime-kuma" = {
+          useTemplate = ["production"];
+          recursive = "zfs";
+        };
+        # rootfs.
+        "zroot/ROOT/nixos" = {
+          useTemplate = ["production"];
+          recursive = "zfs";
+        };
+        # nix stuff, just to make sure.
+        "zroot/nix" = {
+          useTemplate = ["production"];
+          recursive = "zfs";
+        };
+      };
+    };
+
     # TS is enabled in the imported module, this is additional config.
     tailscale = {
       useRoutingFeatures = "both";

nix/hosts/t14/configuration.nix

@@ -14,6 +14,7 @@
     ../../modules/base.nix
     ../../modules/dnscrypt.nix
     ../../modules/firejail.nix
+    ../../modules/sanoid.nix
     ../../modules/zram.nix
   ];
 
@@ -333,6 +334,27 @@
       ];
     };
 
+    sanoid = {
+      enable = true;
+      interval = "*:0/5";
+      datasets = {
+        "zroot/userdata" = {
+          useTemplate = ["frequent"];
+          recursive = "zfs";
+        };
+        "zroot/system/nixos" = {
+          useTemplate = ["production"];
+          recursive = "zfs";
+        };
+        "zroot/local/nix" = {
+          useTemplate = ["production"];
+        };
+        "zroot/local/xper" = {
+          useTemplate = ["production"];
+        };
+      };
+    };
+
     syncthing = {
       enable = true;
       openDefaultPorts = true;

nix/modules/sanoid.nix

@@ -0,0 +1,45 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}: {
+  services.sanoid = {
+    templates = {
+      production = {
+        frequently = 5;
+        hourly = 96;
+        daily = 30;
+        monthly = 3;
+        yearly = 0;
+        autosnap = true;
+        autoprune = true;
+      };
+
+      frequent = {
+        frequently = 90;
+        frequent_period = 5;
+        hourly = 96;
+        daily = 30;
+        monthly = 3;
+        yearly = 0;
+        autosnap = true;
+        autoprune = true;
+      };
+    };
+  };
+
+  systemd.timers.sanoid.timerConfig = {
+    Persistent = true;
+    # WantedBy =["timers.target"];
+  };
+
+  environment.systemPackages = with pkgs; [
+    mbuffer
+    zstd
+  ];
+
+  users.users.root.openssh.authorizedKeys.keys = [
+    "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIOrlXIj3oWbWrFUZnhccd/uqM2D/yRiKOEwfD6xbngJ7 syncoid pull backups"
+  ];
+}