nixos-rustdesk-systemd-service-working

    networking.firewall = {
      # 8000 = Rustdesk?
      # 21115-21117 = Rustdesk  https://rustdesk.com/docs/en/self-host/
      # 21118 and 21119 = Rustdesk Web Client
      allowedUDPPorts = [ ... 22 21116 ... ];
      allowedTCPPorts = [ ... 22 8000 21115 21116 21117 21118 21119 ... ];
    };

    systemd.tmpfiles.rules = [
      "d /opt/rustdesk 0700 root root"
      "d /var/log/rustdesk 0700 root root"
      # optional (only for [Erase Your Darlings](https://grahamc.com/blog/erase-your-darlings) or [tmpfs as root](https://elis.nu/blog/2020/05/nixos-tmpfs-as-root/) setups):
      "L /opt/rustdesk/db_v2.sqlite3 - - - - /persist/opt/rustdesk/db_v2.sqlite3"
      "L /opt/rustdesk/db_v2.sqlite3-shm - - - - /persist/opt/rustdesk/db_v2.sqlite3-shm"
      "L /opt/rustdesk/db_v2.sqlite3-wal - - - - /persist/opt/rustdesk/db_v2.sqlite3-wal"
      "L /opt/rustdesk/id_ed25519 - - - - /persist/opt/rustdesk/id_ed25519"
      "L /opt/rustdesk/id_ed25519.pub - - - - /persist/opt/rustdesk/id_ed25519.pub"
    ];

    systemd.services.rustdesksignal = {
      description = "Rustdesk Signal Server (hbbs)";
      documentation = [
        "https://rustdesk.com/docs/en/self-host/rustdesk-server-oss/install/"
        "https://github.com/techahold/rustdeskinstall/blob/master/install.sh"
      ];
      after = [ "network-pre.target" ];
      wants = [ "network-pre.target" ];
      partOf = [ "rustdeskrelay.service" ];
      wantedBy = [ "multi-user.target" ];
      serviceConfig = {
        Type = "simple";
        LimitNOFILE=1000000;
        WorkingDirectory="/opt/rustdesk";
        StandardOutput="append:/var/log/rustdesk/hbbs.log";
        StandardError="append:/var/log/rustdesk/hbbs.error";
        ExecStart="${pkgs.rustdesk-server}/bin/hbbs -k _";
        Restart="always";
        RestartSec=10;
      };
      #script = with pkgs; ''
      #'';
    };

    systemd.services.rustdeskrelay = {
      description = "Rustdesk Relay Server (hbbr)";
      documentation = [
        "https://rustdesk.com/docs/en/self-host/rustdesk-server-oss/install/"
        "https://github.com/techahold/rustdeskinstall/blob/master/install.sh"
      ];
      after = [ "network-pre.target" ];
      wants = [ "network-pre.target" ];
      partOf = [ "rustdesksignal.service" ];
      wantedBy = [ "multi-user.target" ];
      serviceConfig = {
        Type = "simple";
        LimitNOFILE=1000000;
        WorkingDirectory="/opt/rustdesk";
        StandardOutput="append:/var/log/rustdesk/hbbr.log";
        StandardError="append:/var/log/rustdesk/hbbr.error";
        ExecStart="${pkgs.rustdesk-server}/bin/hbbr -k _";
        Restart="always";
        RestartSec=10;
      };
      #script = with pkgs; ''
      #'';
    };