* see also https://www.bachmann-lan.de/raspberry-pi-mit-wireguard-als-vpn-server-mit-wireguard/
  * lokale Kopie {{:raspberry_pi_mit_wireguard_als_vpn_server_bachmann-lan.de_2020-04-10_21_05_58_.html}}

  apt install -y linux-headers-current-sunxi qrencode dirmngr
  apt install -y wireguard-tools