Distribution-specific configuration methods

NetworkManager is used by many distributions on desktop systems, but many Linux distributions have also used custom network configuration files and scripts. Some still use them, while other systems migrated to NetworkManager but maintain old methods as an alternative or in legacy long-term support releases.

Debian

In Debian, the configuration file for network interfaces is /etc/network/interfaces. Unlike NetworkManager’s native format, this allows keeping configurations for all interfaces in a single file. To make the configuration more modular and easier to read, it is possible to store files for individual interfaces in the /etc/network/interfaces.d/ directory.

Interface configurations are also identified by link names rather than arbitrary descriptions and UUIDs. This is how to set an onboard Ethernet device, eno1, to use static addresses for both IPv4 and IPv6, for example:

iface eno1 inet static
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