Network Configurator

Overview

network-configurator is a network configuration tool for Linux systems using systemd-networkd. It allows creating and modifying network configuration interactively or via command-line commands.

The main goal is to simplify RecoveryBox deployment and maintenance by automating network configuration file generation without manual manipulation.

Key features include:

configuration of physical or virtual network interfaces;
bridge creation;
linking physical interfaces to a bridge;
persistent network interface renaming based on MAC address;
Wi-Fi interface configuration in client mode;
automatic addition of WAN interfaces to the firewall configuration;
display of interface status and current configuration.

The tool works both via an interactive menu and in non-interactive mode for integration into installation or automation scripts.

How it works

The script relies on systemd-networkd and automatically generates configuration files in /etc/systemd/network.

File organization follows systemd's priority convention:

Prefix	Type
`10-*.link`	interface renaming
`20-*.netdev`	virtual interface creation (bridges)
`30-*.network`	interface network configuration

Changes made by the configurator are only applied after restarting systemd-networkd (or the system for .link files).

The script has two operating modes:

Usage Guide

Interactive mode

Without arguments, a menu allows:

viewing interface status;
displaying current configuration;
configuring an interface;
configuring a Wi-Fi interface;
creating bridge ↔ interface associations;
renaming physical interfaces.

The different steps guide the user and perform necessary checks before writing files.

Command-line mode

The script can be run without going through the interactive interface. Each action is available as a command, enabling use in installation or automation scripts (Ansible, AWX, post-installation scripts, etc.).

General syntax

network-configurator <command> [arguments]

CreateBridge

Creates a virtual interface of type bridge.

Syntax

network-configurator CreateBridge <bridge>

Arguments

Argument	Description
`<bridge>`	Name of the bridge to create.

Example

network-configurator CreateBridge Lan

GetPhysicalInterfaces

Displays all detected physical network interfaces and their status.

Syntax

network-configurator GetPhysicalInterfaces

No arguments expected.

GetVInterfacesConfig

Displays the generated network configuration.

Syntax

network-configurator GetVInterfacesConfig [interface]

Arguments

Argument	Description
`interface`	(optional) Name of the interface to display. If absent, all configurations are displayed.

Examples

network-configurator GetVInterfacesConfig

network-configurator GetVInterfacesConfig Wan

RenameInterface

Permanently renames a network interface based on its MAC address.

Syntax

network-configurator RenameInterface <mac-address> <new-name>

Arguments

Argument	Description
`<mac-address>`	MAC address of the interface.
`<new-name>`	New name to assign.

Example

network-configurator RenameInterface 00:11:22:33:44:55 Wan

LinkInterface

Opens the interactive menu for linking or unlinking physical interfaces to existing bridges.

Syntax

network-configurator LinkInterface

No arguments.

SetInterface

Creates or directly modifies an interface configuration.

Syntax

network-configurator SetInterface \
    <interface> \
    <dhcp> \
    <address> \
    <gateway> \
    <dns> \
    <network-options> \
    <dhcpv4-options> \
    <ipv6acceptra-options>

Arguments

Argument	Description
`<interface>`	Name of the interface to configure.
`<dhcp>`	`yes` or `no`.
`<address>`	IP address with mask (`192.168.1.10/24`). Ignored if DHCP=`yes`.
`<gateway>`	Default gateway.
`<dns>`	Space-separated list of DNS servers. Use `no` to skip DNS directive.
`<network-options>`	Additional options for the `[Network]` section. Use `no` if none.
`<dhcpv4-options>`	Content of the `[DHCPv4]` section. Use `no` if none.
`<ipv6acceptra-options>`	Content of the `[IPv6AcceptRA]` section. Use `no` if none.

DHCP Example

network-configurator SetInterface Wan yes "" "" "1.1.1.1 9.9.9.9" no no no

Static IP Example

network-configurator SetInterface \
    Lan \
    no \
    192.168.10.1/24 \
    192.168.10.254 \
    "1.1.1.1 9.9.9.9" \
    no \
    no \
    no

MenuSetInterface

Launches the interactive interface configuration menu.

Syntax

network-configurator MenuSetInterface <interface>

Arguments

Argument	Description
`<interface>`	Interface to configure.

MenuRenameInterface

Launches the interactive interface renaming menu.

Syntax

network-configurator MenuRenameInterface [name]

If a name is provided, it is automatically suggested as the new name.

MenuSetVlan

Configures a Wi-Fi interface in client mode.

Syntax

network-configurator MenuSetVlan

The wizard then asks for:

the SSID;
the password;
then automatically configures wpa_supplicant.

ApplyChanges

Proposes restarting systemd-networkd to apply changes.

Syntax

network-configurator ApplyChanges

status

Displays the current status of:

bridges;
physical interfaces;
interfaces linked to each bridge.

Syntax

network-configurator status

help

Displays the built-in help.

Syntax

network-configurator help

Configuration Files

The configurator modifies several system files.

systemd-networkd configuration

All files are created in:

/etc/systemd/network/

Renamed interfaces

10-<interface>.link

Contains:

the interface MAC address;
the new assigned name.

Example:

[Match]
MACAddress=00:11:22:33:44:55

[Link]
Name=Wan

Bridges

20-<bridge>.netdev

Declares virtual bridge interfaces.

Network configuration

30-<interface>.network

Describes:

DHCP or static IP;
DNS;
gateway;
advanced systemd-networkd options;
optional bridge attachment.

Wi-Fi configuration

Wi-Fi interfaces use:

/etc/wpa_supplicant/wpa_supplicant-<interface>.conf

The configurator automatically adds selected networks via wpa_cli.

Firewall configuration

When the user indicates that an interface is a WAN interface, the script automatically modifies:

/etc/iptables/iptables.sh

to add this interface to the WAN variable.

The iptables service is then restarted.

Backups

Before any modification, the configurator automatically creates a backup of existing files:

<file>.bak

These backups allow manual restoration in case of problems.

Debugging

Several commands allow verifying the configurator's operation.

Check interfaces

network-configurator status

Displays:

bridges;
physical interfaces;
interfaces linked to each bridge.

Check generated configuration

network-configurator GetVInterfacesConfig

or

cat /etc/systemd/network/*.network

Check systemd-networkd status

systemctl status systemd-networkd

Reload configuration

The configurator can automatically restart systemd-networkd, but it is also possible to do it manually:

systemctl restart systemd-networkd

Check interface renaming

.link files are applied by systemd-networkd.

Check Wi-Fi configuration

wpa_cli -i <interface> status

or

systemctl status wpa_supplicant@<interface>

Check firewall configuration

After adding a WAN interface:

grep WAN= /etc/iptables/iptables.sh

then:

systemctl status iptables

to confirm that the configuration has been reloaded.

Useful logs

In case of problems, the following logs are particularly useful:

journalctl -u systemd-networkd

journalctl -u wpa_supplicant@<interface>

journalctl -u iptables

They help diagnose network configuration or application errors.