Adding a polkit-service to fix networkmanager

[Adam Mazurkiewicz]

I installed networkmanager in my Xfce Desktop Environment, but it did
not allow to add new connections. A message was "Insufficient
privileges". After some googling I got to conclusion that the polkit
service is needed to fix it. Now I am trying to add the polkit-service
in the way I have seen at some config.scm examples from Google but an
error "guix system: error: more than one target service of type
'polkit'" is appearing.

I am a total newbe and I do not understand it. Help me please. Here
you are my config.scm:

(use-modules
  (gnu)
  (gnu system)
  (gnu system nss)
  (gnu packages gnuzilla)
  (gnu packages libusb)
  (gnu packages cups)
  (gnu packages guile-xyz)
  (gnu packages emacs-xyz)
  (gnu packages admin)
  (gnu packages polkit)
  (guix monads)
  (guix store)
             (gnu services networking)
             (gnu services audio)
             (gnu packages linux)
             (gnu services dbus)
  (gnu services desktop)
  (srfi srfi-1))

(use-service-modules
 desktop base xorg ssh avahi dbus networking cups mcron virtualization
 web pm nfs)

(use-package-modules
 avahi xorg certs wm code wget admin emacs tmux
 ssh linux disk file gnuzilla version-control maths guile crypto gnupg
 password-utils rsync suckless gnome video xdisorg
 terminals ssh image-viewers web-browsers pulseaudio
 tor readline adns fontutils gnunet package-management
 networking connman lisp cryptsetup fonts python
 bittorrent engineering graphviz shells compression
 gnome enlightenment dns ghostscript kde-frameworks bash backup nfs)

(operating-system
  (host-name "s")
  (timezone "Europe/Paris")
  (locale "en_US.utf8")


  (bootloader
    (bootloader-configuration
      (bootloader grub-bootloader)
        (target "/dev/sda")
        (menu-entries
          (list
            (menu-entry
              (label "Debianek")
              (linux "(hd0,6)/boot/v")
              (linux-arguments '("root=/dev/sda6 ro"))
              (initrd "(hd0,6)/boot/i"))))))



  (file-systems (cons (file-system
                        (device (file-system-label "guixsd"))
                        (mount-point "/")
                        (type "ext4"))
                      %base-file-systems))

  (users (cons (user-account
                (name "s")
                (comment "QUIT")
                (group "users")
                (supplementary-groups '("wheel" "netdev"
                                        "audio" "video"))
                (home-directory "/home/s"))
               %base-user-accounts))

  ;; This is where we specify system-wide packages.
  (packages (cons* icecat
    libvdpau-va-gl
    network-manager
    network-manager-applet
    network-manager-openvpn
    networkmanager-qt
                                        ;useful tools
    avahi zip unzip tmux htop tree mosh mcron
    the-silver-searcher psmisc wget file strace
    inotify-tools wgetpaste rsync dmenu openssh lsh
    feh stow mcelog readline libcap wcalc graphviz xdotool
    sudo
    ;; gvfs ; for automounting as user, check gvfsd as a service before
    ;; enabling

                                        ; fstools
    dosfstools nfs-utils
                                        ; X
    xbindkeys xterm  xmodmap setxkbmap  xclip xkill xbacklight
    xev xdpyinfo xrdb xrandr xfontsel
    gs-fonts font-wqy-zenhei
    font-wqy-microhei
    font-adobe-source-han-sans
    font-inconsolata

                                        ; audio
    pulseaudio pulsemixer

                                        ; laptop specific
    acpi cpupower ;;(TODO:cpupower... wat?)

                                        ; dev
    gnu-make python-3 binutils
    guile-lib

                                        ; misc tools
    units gnuplot

                                        ; terminals and emulators
    st termite fish bash bash-completion

                                        ; Networking, crypto & security
    gnupg pwgen tor torsocks nmap adns iodine
    connman transmission pinentry pinentry-gtk2

                                        ;for HTTPS access
    nss-certs

                                        ; emacs
    emacs emacs-guix emacs-magit-popup emacs-smart-mode-line
    emacs-rainbow-delimiters emacs-rainbow-identifiers
    emacs-rainbow-blocks
    emacs-scheme-complete emacs-neotree emacs-ag emacs-flycheck
    emacs-undo-tree emacs-fill-column-indicator
    emacs-yasnippet emacs-yasnippet-snippets
    emacs-scheme-complete emacs-danneskjold-theme
    geiser guile-2.2 paredit emacs-debbugs
    emacs-bash-completion emacs-linum-relative
    emacs-youtube-dl emacs-writegood-mode emacs-symon emacs-smartparens
    emacs-rfcview

    emacs-ghub
    emacs-magit
    emacs-org2web

                   %base-packages))

  (services (cons* (gnome-desktop-service)
                   (xfce-desktop-service)
                   (console-keymap-service "pl")
                   (polkit-service)
                   %desktop-services))

  ;; Allow resolution of '.local' host names with mDNS.
  (name-service-switch %mdns-host-lookup-nss))