After doing the
sudo /etc/init.d/networking stop/restart The network will be stopped. and the appearance of the ubuntu will change. and then, I can not start the network again, unless I restart the ubuntu. It can not logout; and Should only shutdown by the power key.
These are other related commands:
$ sudo /etc/init.d/networking start [sudo] password: Rather than invoking init scripts through /etc/init.d, use the service(8) utility, e.g. service networking start Since the script you are attempting to invoke has been converted to an Upstart job, you may also use the start(8) utility, e.g. start networking networking stop/waiting $ sudo service networking start networking stop/waiting