1) First, we'll check our current status and linux names of interfaces
ip a
or
ip link
where commands lists our' machine network interfaces, for example:
2) Next, using the subcommand addr we will add an IP address with a proper nework mask length
ip addr add 192.168.1.10/24 dev [INTERFACE_NAME]
for example:
ip addr add 192.168.1.10/24 dev eth1
3) No we will add default gateway's IP address for correct routing
ip route add default via [GATEWAY_ADDRESS]
in our case for example:
ip route add default via 192.168.1.1
4) and finally start up the interface
ip link set [INTERFACE_NAME] up
for example for eth1 interface:
ip link set eth1 up
5) And at last, check of corectness:
ip a