systemd Developer Tom Gundersen teg@jklm.no systemd-networkd.service 8 systemd-networkd.service systemd-networkd Network manager systemd-networkd.service /usr/lib/systemd/systemd-networkd systemd-networkd is a system service that manages networks. It detects and configures network devices as they appear. Network devices are managed by networkd only if they have the udev tag systemd-networkd. Network configurations applied before networkd is started are not removed, and configuration applied by networkd are not removed when networkd exits. This ensures restarting networkd does not cut the network connection, and in particular that it is safe to transition between the initrd and the real root, and back. The network files are read from the files located in the system network directory /usr/lib/systemd/network, the volatile runtime network directory /run/systemd/network and the local administration network directory /etc/systemd/network. All link files are collectively sorted and processed in lexical order, regardless of the directories in which they live. However, files with identical filenames replace each other. Files in /etc have the highest priority, files in /run take precedence over files with the same name in /lib. This can be used to override a system-supplied network file with a local file if needed; a symlink in /etc with the same name as a network file in /lib, pointing to /dev/null, disables the network file entirely. Network files must have the extension .network; other extensions are ignored. The network file contains a [Match] section, which determines if a given network file may be applied to a given device; and a [Network] section specifying how the device should be configured. The first (in lexical order) of the network files that matches a given device is applied. A network file is said to match a device if each of the entries in the [Match] section matches, or if the section is empty. The following keys are accepted: MACAddress The hardware address. Path The persistent path, as exposed by the udev property ID_PATH. Driver The driver currently bound to the device, as exposed by the udev property DRIVER. Type The device type, as exposed by the udev property DEVTYPE. Name The device name, as exposed by the udev property INTERFACE. The [Network] section accepts the following keys: Description A description of the device. This is only used for presentation purposes. Address A static IPv4 or IPv6 address and its prefix length, separated by a '/' character. The format of the address must be as described in inet_pton3 . Gateway The gateway address, which must be in the format described in inet_pton3 . systemd1, udev7,