Answer:
ifconfig -a
Explanation:
ifconfig is used to configure the system's kernel-resident network interfaces. It is used at boot time to set up interfaces as necessary. After that, it is usually only needed when debugging, or when system tuning is needed. If no arguments are given, ifconfig displays the status of the system's active interfaces.
-a display all interfaces which are currently available, even if down. source manpages: ifconfig.
