systemd-networkd - Arch - Ubuntu - RHEL

A systemd network tool:

networkctl

Disable Network Manager and enable systemd-networkd.

sudo systemctl disable NetworkManager
sudo systemctl enable systemd-networkd

This network configuration directory will need to exist. Create it:

sudo mkdir /etc/systemd/network

Any NIC that matches this pattern will be configured to use DHCP:

sudo vi /etc/systemd/network/20-wired.network

[Match]
Name=enp3*

[Network]
DHCP=yes

This specific NIC will be configured with the static IP specified:

sudo vi /etc/systemd/network/10-wired.network

[Match]
Name=enp3s0

[Network]
Address=192.168.3.25/24
Gateway=192.168.3.1
DNS=8.8.8.8

You can restart systemd-networkd after making any changes.

sudo systemctl restart systemd-networkd

Bridged Interfaces

Here is an example of creating a device for a bridge interface:

sudo vi /etc/systemd/network/bridge-br0.netdev

[NetDev]
Name=br0
Kind=bridge

This would add a NIC to a bridged interface:

sudo vi /etc/systemd/network/bridge-br0-slave.network

[Match]
Name=eth1

[Network]
Bridge=br0

This would define the static IP info for a bridged interface:

sudo vi /etc/systemd/network/bridge-br0.network

[Match]
Name=br0

[Network]
Address=192.168.3.25/24
Gateway=192.168.3.1
DNS=8.8.8.8

Wifi

A wireless interface might be configured like this:

/etc/systemd/network/25-wireless.network

[Match]
Name=wlp2s0

[Network]
DHCP=yes
IgnoreCarrierLoss=3s

More Info

systemd-networkd-wait-online

Set a priority if you have more than one interface:

[DHCPv4]
RouteMetric=20
[IPv6AcceptRA]
RouteMetric=20