Commit 21529d18 authored by Bjørn Forsman's avatar Bjørn Forsman
Browse files

nixos/ups: shutdown UPS at host shutdown 

Implement the missing bit of the NUT shutdown design[1]. This ensures
that machines come back up automatically after a power outage. (Without
this change they will only come back up if the UPS completely empties
its battery.)

[1] https://networkupstools.org/docs/user-manual.chunked/Configuration_notes.html#Shutdown_design
parent 3b781a1e

nixos/modules/services/monitoring/ups.nix

+20 −0
Original line number Diff line number Diff line
@@ -311,6 +311,7 @@ let 
            MINSUPPLIES = 1;

            MONITOR = <generated from config.power.ups.upsmon.monitor>

            NOTIFYCMD = "''${pkgs.nut}/bin/upssched";

            POWERDOWNFLAG = "/run/killpower";

            RUN_AS_USER = "root";

            SHUTDOWNCMD = "''${pkgs.systemd}/bin/shutdown now";

          }
@@ -334,6 +335,7 @@ let 
        MINSUPPLIES = lib.mkDefault 1;

        MONITOR = lib.flip lib.mapAttrsToList cfg.upsmon.monitor (name: monitor: with monitor; [ system powerValue user "\"@upsmon_password_${name}@\"" type ]);

        NOTIFYCMD = lib.mkDefault "${pkgs.nut}/bin/upssched";

        POWERDOWNFLAG = lib.mkDefault "/run/killpower";

        RUN_AS_USER = "root"; # TODO: replace 'root' by another username.

        SHUTDOWNCMD = lib.mkDefault "${pkgs.systemd}/bin/shutdown now";

      };
@@ -575,6 +577,24 @@ in 
      ];

    };



    systemd.services.ups-killpower = lib.mkIf (cfg.upsmon.settings.POWERDOWNFLAG != null) {

      enable = cfg.upsd.enable;

      description = "UPS Kill Power";

      wantedBy = [ "shutdown.target" ];

      after = [ "shutdown.target" ];

      before = [ "final.target" ];

      unitConfig = {

        ConditionPathExists = cfg.upsmon.settings.POWERDOWNFLAG;

        DefaultDependencies = "no";

      };

      environment = envVars;

      serviceConfig = {

        Type = "oneshot";

        ExecStart = "${pkgs.nut}/bin/upsdrvctl shutdown";

        Slice = "system-ups.slice";

      };

    };



    environment.etc = {

      "nut/nut.conf".source = pkgs.writeText "nut.conf"

        ''