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Diffstat (limited to 'nixos/modules/services/backup/sanoid.nix')
-rw-r--r-- | nixos/modules/services/backup/sanoid.nix | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/nixos/modules/services/backup/sanoid.nix b/nixos/modules/services/backup/sanoid.nix new file mode 100644 index 000000000000..0472fb4ba1e7 --- /dev/null +++ b/nixos/modules/services/backup/sanoid.nix @@ -0,0 +1,213 @@ +{ config, lib, pkgs, ... }: + +with lib; + +let + cfg = config.services.sanoid; + + datasetSettingsType = with types; + (attrsOf (nullOr (oneOf [ str int bool (listOf str) ]))) // { + description = "dataset/template options"; + }; + + # Default values from https://github.com/jimsalterjrs/sanoid/blob/master/sanoid.defaults.conf + + commonOptions = { + hourly = mkOption { + description = "Number of hourly snapshots."; + type = types.ints.unsigned; + default = 48; + }; + + daily = mkOption { + description = "Number of daily snapshots."; + type = types.ints.unsigned; + default = 90; + }; + + monthly = mkOption { + description = "Number of monthly snapshots."; + type = types.ints.unsigned; + default = 6; + }; + + yearly = mkOption { + description = "Number of yearly snapshots."; + type = types.ints.unsigned; + default = 0; + }; + + autoprune = mkOption { + description = "Whether to automatically prune old snapshots."; + type = types.bool; + default = true; + }; + + autosnap = mkOption { + description = "Whether to automatically take snapshots."; + type = types.bool; + default = true; + }; + + settings = mkOption { + description = '' + Free-form settings for this template/dataset. See + <link xlink:href="https://github.com/jimsalterjrs/sanoid/blob/master/sanoid.defaults.conf"/> + for allowed values. + ''; + type = datasetSettingsType; + }; + }; + + commonConfig = config: { + settings = { + hourly = mkDefault config.hourly; + daily = mkDefault config.daily; + monthly = mkDefault config.monthly; + yearly = mkDefault config.yearly; + autoprune = mkDefault config.autoprune; + autosnap = mkDefault config.autosnap; + }; + }; + + datasetOptions = { + useTemplate = mkOption { + description = "Names of the templates to use for this dataset."; + type = (types.listOf (types.enum (attrNames cfg.templates))) // { + description = "list of template names"; + }; + default = []; + }; + + recursive = mkOption { + description = "Whether to recursively snapshot dataset children."; + type = types.bool; + default = false; + }; + + processChildrenOnly = mkOption { + description = "Whether to only snapshot child datasets if recursing."; + type = types.bool; + default = false; + }; + }; + + datasetConfig = config: { + settings = { + use_template = mkDefault config.useTemplate; + recursive = mkDefault config.recursive; + process_children_only = mkDefault config.processChildrenOnly; + }; + }; + + # Extract pool names from configured datasets + pools = unique (map (d: head (builtins.match "([^/]+).*" d)) (attrNames cfg.datasets)); + + configFile = let + mkValueString = v: + if builtins.isList v then concatStringsSep "," v + else generators.mkValueStringDefault {} v; + + mkKeyValue = k: v: if v == null then "" + else generators.mkKeyValueDefault { inherit mkValueString; } "=" k v; + in generators.toINI { inherit mkKeyValue; } cfg.settings; + + configDir = pkgs.writeTextDir "sanoid.conf" configFile; + +in { + + # Interface + + options.services.sanoid = { + enable = mkEnableOption "Sanoid ZFS snapshotting service"; + + interval = mkOption { + type = types.str; + default = "hourly"; + example = "daily"; + description = '' + Run sanoid at this interval. The default is to run hourly. + + The format is described in + <citerefentry><refentrytitle>systemd.time</refentrytitle> + <manvolnum>7</manvolnum></citerefentry>. + ''; + }; + + datasets = mkOption { + type = types.attrsOf (types.submodule ({ config, ... }: { + options = commonOptions // datasetOptions; + config = mkMerge [ (commonConfig config) (datasetConfig config) ]; + })); + default = {}; + description = "Datasets to snapshot."; + }; + + templates = mkOption { + type = types.attrsOf (types.submodule ({ config, ... }: { + options = commonOptions; + config = commonConfig config; + })); + default = {}; + description = "Templates for datasets."; + }; + + settings = mkOption { + type = types.attrsOf datasetSettingsType; + description = '' + Free-form settings written directly to the config file. See + <link xlink:href="https://github.com/jimsalterjrs/sanoid/blob/master/sanoid.defaults.conf"/> + for allowed values. + ''; + }; + + extraArgs = mkOption { + type = types.listOf types.str; + default = []; + example = [ "--verbose" "--readonly" "--debug" ]; + description = '' + Extra arguments to pass to sanoid. See + <link xlink:href="https://github.com/jimsalterjrs/sanoid/#sanoid-command-line-options"/> + for allowed options. + ''; + }; + }; + + # Implementation + + config = mkIf cfg.enable { + services.sanoid.settings = mkMerge [ + (mapAttrs' (d: v: nameValuePair ("template_" + d) v.settings) cfg.templates) + (mapAttrs (d: v: v.settings) cfg.datasets) + ]; + + systemd.services.sanoid = { + description = "Sanoid snapshot service"; + serviceConfig = { + ExecStartPre = map (pool: lib.escapeShellArgs [ + "+/run/booted-system/sw/bin/zfs" "allow" + "sanoid" "snapshot,mount,destroy" pool + ]) pools; + ExecStart = lib.escapeShellArgs ([ + "${pkgs.sanoid}/bin/sanoid" + "--cron" + "--configdir" configDir + ] ++ cfg.extraArgs); + ExecStopPost = map (pool: lib.escapeShellArgs [ + "+/run/booted-system/sw/bin/zfs" "unallow" "sanoid" pool + ]) pools; + User = "sanoid"; + Group = "sanoid"; + DynamicUser = true; + RuntimeDirectory = "sanoid"; + CacheDirectory = "sanoid"; + }; + # Prevents missing snapshots during DST changes + environment.TZ = "UTC"; + after = [ "zfs.target" ]; + startAt = cfg.interval; + }; + }; + + meta.maintainers = with maintainers; [ lopsided98 ]; + } |