Distribution comparison - network configuration across distros

The same network configuration has different homes on different distributions. This lesson is a tour of where configuration lives on the four major families: Debian, Ubuntu, RHEL, and SUSE.

Quick reference

Ubuntu

Ubuntu uses Netplan as the declarative layer on top of either NetworkManager (desktop) or systemd-networkd (server). The config files live in /etc/netplan/*.yaml.

cat /etc/netplan/*.yaml
nmcli connection show        # if NetworkManager is the renderer
networkctl status eth0        # if networkd is the renderer

Debian

Debian is more flexible (and more confusing) than Ubuntu:

• The installer may configure /etc/network/interfaces (ifupdown).
• A desktop install may use NetworkManager.
• A server install may use systemd-networkd.

The default depends on what the installer detected. Check what is running:

systemctl status networking
systemctl status NetworkManager
systemctl status systemd-networkd

Only one should be active.

RHEL family

RHEL 9, Rocky Linux 9, AlmaLinux 9, Fedora: NetworkManager is the default everywhere. Configuration lives in /etc/NetworkManager/system-connections/ as .nmconnection keyfiles.

cat /etc/NetworkManager/system-connections/eth0.nmconnection
nmcli connection show

To configure from the command line, use nmcli or nmtui. The older system-config-network and direct editing of /etc/sysconfig/network-scripts/ is deprecated on RHEL 9.

SUSE

openSUSE Leap uses Wicked as the traditional manager. Configuration is in /etc/sysconfig/network/. Newer installs may use NetworkManager.

cat /etc/sysconfig/network/ifcfg-eth0
wicked show all

Arch

Arch uses systemd-networkd by default. Configuration is in /etc/systemd/network/ (.network files).

How to choose

In a mixed environment:

1. Standardise on the platform’s default unless there is a reason not to. Fighting the default is a maintenance burden.
2. Document the choice in your host inventory.
3. For server fleets, prefer systemd-networkd or NetworkManager based on the platform default. Do not mix them per-host.
4. If using Netplan on Ubuntu server, use renderer: networkd for predictability. Use renderer: NetworkManager only if the host has Wi-Fi or moves between networks.

Where to look first

On an unknown host:

ls /etc/netplan/ 2>/dev/null
ls /etc/systemd/network/ 2>/dev/null
ls /etc/NetworkManager/system-connections/ 2>/dev/null
ls /etc/network/interfaces 2>/dev/null
ls /etc/sysconfig/network/ 2>/dev/null
systemctl status NetworkManager systemd-networkd networking wicked 2>/dev/null

Whichever file or service exists is the one to read.

Knowledge check