NetworkManager (nmtui)

[jurek]

To see list of saved connections, use (<SavedWiFiConn>)

nmcli c

To see list of available WiFi hotspots (<WiFiSSID>)

nmcli d wifi list

or:

sudo iwlist <WifiInterface> scanning

To see list of interfaces (<WifiInterface>)

ifconfig -a

Just change <WifiInterface>, <WiFiSSID>, <WiFiPassword> in the following commands to reflect your setup. If WiFi info already saved, easier way using <SavedWiFiConn> name of connection as it was saved in NetworkManager.
Ubuntu 16.04

##disconnect
nmcli d disconnect <WifiInterface>

##connect
nmcli d connect <WifiInterface>

Another way:

##disconnect
nmcli c down <SavedWiFiConn>

##connect
nmcli c up <SavedWiFiConn>

Ubuntu 15.10 & previous

##disconnect
nmcli d disconnect iface <WifiInterface>

##connect
nmcli d wifi connect <WiFiSSID> password <WiFiPassword> iface <WifiInterface>

Another way:

##disconnect:
nmcli c down id <SavedWiFiConn>

##connect:
nmcli c up id <SavedWiFiConn>

If your password isn't automatically recognized type this:

nmcli -a c up <SavedWiFiConn>




nmtui ncurses solution

Great interactive ncurses network manager option:

nmtui

If for some reason it is not installed, the Debian package is:

sudo apt install network-manager

Comes in the same package as nm-applet (the default top bar icon thing) and nm-cli, and is therefore widely available.





If your wi-fi access point is saved, it will auto-connect. Turn wireless on or off with a simpler command:

nmcli nm wifi on
nmcli nm wifi off

on newer version:

nmcli radio wifi on
nmcli radio wifi off