systemd
/etc/systemd/network/wired.network
[Match]
Name=enp1s0
[Link]
RequiredForOnline=routable
[Network]
Address=192.168.122.123/24
Gateway=192.168.122.1
DNS=192.168.122.1ifupdown
/etc/network/interfaces
Static
allow-hotplug enp1s0
iface enp1s0 inet static
address 192.168.1.2
netmask 255.255.255.0
gateway 192.168.1.1DHCP
allow-hotplug enp1s0
iface enp1s0 inet dhcp