zfox1. lépés:
-tök üres volt a file
egy másikban (*nm-system-settings.conf)ez volt :
# This file is installed into /etc/NetworkManager, and is loaded by
# NetworkManager by default. To override, specify: '--config file'
# during NM startup. This can be done by appending to DAEMON_OPTS in
# the file:
#
# /etc/default/NetworkManager
#
[main]
plugins=ifupdown,keyfile
[ifupdown]
managed=false