NetworkManager

NetworkManager is a high level network administration tool.

Installation

Usage

nmcli(1) and nmtui(1) are bundled with NetworkManager.

NetworkManager stores profiles of connections. These are then written to files in /etc/NetworkManager/system-connections/.

To list all connections, try:

nmcli connection show

To set a connection up or down, try:

nmcli connection up CONNECTION_UUID
nmcli connection down CONNECTION_UUID

To delete a connection (and erase the locally stored profile), try:

nmcli connection delete CONNECTION_UUID
# or
rm /etc/NetworkManager/system-connections/CONNECTION_UUID

WiFi

To list available Wi-Fi networks, try:

nmcli device wifi list

To connect to a new Wi-Fi network, thereby creating a connection, try:

nmcli device wifi connect NETWORK_SSID password NETWORK_PASSWORD

To turn off Wi-Fi entirely, try:

nmcli radio wifi off

Network Interfaces

To disconnect a network interface (like eth0), try:

nmcli device disconnect ifname IFNAME

Configurations

DHCP

NetworkManager uses an internal DHCP client. To use a different client, edit /etc/NetworkManager/conf.d/dhcp-client.conf like:

[main]
dhcp=dhclient

Only dhclient and dhcpcd are allowed alternatives.

NetworkManager broadcasts a machine's hostname. To disable this on a per-connection basis, edit /etc/NetworkManager/system-connections/CONNECTION_UUID like:

[ipv4]
dhcp-send-hostname=false

[ipv6]
dhcp-send-hostname=false

DNS

NetworkManager tries to take ownership of DNS through the resolver file, /etc/resolv.conf. If another service tries to do the same, DNS can end up mangled.

To use a different client, edit /etc/NetworkManager/conf.d/dns.conf like:

[main]
dns=dnsmasq

Only dnsmasq and systemd-resolved are allowed alternatives.

== Wi-Fi Backend ===

To use iwd(8) as the Wi-Fi backend, edit /etc/NetworkManager/conf.d/wifi_backend.conf like:

[device]
wifi.backend=iwd

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