What's the "right way" to restart services in 11.10? [duplicate]

For Desktops

Try

sudo service network-manager restart

Or on recent Ubuntu versions:

sudo systemctl restart systemd-networkd

instead.

Ubuntu uses network-manager instead of the traditional Linux networking model. so you should restart the network-manager service instead of the network service. Or use ifup/down.

For Servers

Check this answer.

For Servers

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

You could try

ifconfig eth0 down && ifconfig eth0 up

(or whatever your network interface is called) to restart the network.

ubuntu CLI: to restart the network service either

sudo /etc/init.d/networking restart

or

ifdown eth0
ifup eth0