Debian can automatically set up the networking based on the contents of "/etc/network/interfaces.d/" files. For example, to enable DHCP for "eth0" by default on startup:
echo "auto eth0 iface eth0 inet dhcp" > /etc/network/interfaces.d/eth0
To set up a static IP:
echo "auto eth0 iface eth0 inet static address 192.168.0.50 netmask 255.255.255.0 gateway 192.168.0.1" > /etc/network/interfaces.d/eth0 echo "nameserver 126.96.36.199" > /etc/resolv.conf
To make this take effect immediately for either option:
service networking restart
To configure other interfaces, replace "eth0" with the other network device name. Some interfaces may use predictable interface names. For example, the traditional name for an ethernet port might be "eth1", but some devices may use "enp1s0" for PCIe, or "enx00D069C0FFEE" (the MAC address appended) for USB ethernet interfaces. Run 'ifconfig -a' or 'ip a' to get a complete list of interfaces, including the ones that are not configured.