sudo service network-manager restart
Restarting networking on a desktop machine will cause dbus and a bunch of service to stop and never be started again, usually leading to the whole system being unusable.
As Ubuntu does event based network bring up, there quite simply isn't a way to undo it all and redo it all, so a restart just isn't plain possible. The recommended way instead is to use ifdown and ifup on the interfaces you actually want to reconfigure:
sudo ifdown --exclude=lo -a && sudo ifup --exclude=lo -a