Nmcli

nmcli is NetworkManager's built-in command-line interface added in 2010, it is used at least in RHEL. nmcli allows easy display of NetworkManager's current status, manage at least Ethernet and WiFi connections and devices, monitor connections.

Basic Commands

See RHEL 8.0 official documentation: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html-single/configuring_and_managing_networking/index

• Show network connections:

nmcli connection show
  NAME       UUID                                  TYPE      DEVICE
Profile 1  db1060e9-c164-476f-b2b5-caec62dc1b05  ethernet    ens3
bond0       aaf6eb56-73e5-4746-9037-eed42caa8a65  ethernet    --

nmcli connection show
NAME                UUID                                  TYPE      DEVICE
System eth0         5fb06bd0-0bb0-7ffb-45f1-d6edd65f3e03  ethernet  eth0
System eth1         9c92fad9-6ecb-3e6c-eb4d-8a47c6f50c04  ethernet  eth1
Wired connection 1  c40205e6-e5f8-37ba-a85b-ef94a15aad79  ethernet  --

• nmcli connection show --active

nmcli device status
DEVICE  TYPE      STATE      CONNECTION
ens3    ethernet  connected  Profile 1
ens4    ethernet  disconnected  --
lo      loopback  unmanaged  --

nmcli device status
DEVICE  TYPE      STATE      CONNECTION
eth0    ethernet  connected  System eth0
eth1    ethernet  connected  System eth1
lo      loopback  unmanaged  --

• nmcli device show (Includes link or carrier status). See also: ethtool

GENERAL.DEVICE:                         ens33
GENERAL.TYPE:                           ethernet
GENERAL.HWADDR:                         00:0C:29:54:F7:20
GENERAL.MTU:                            1500
GENERAL.STATE:                          100 (connected)
GENERAL.CONNECTION:                     ens33
GENERAL.CON-PATH:                       /org/freedesktop/NetworkManager/ActiveConnection/5
WIRED-PROPERTIES.CARRIER:               on
IP4.ADDRESS[1]:                         192.168.219.150/24
IP4.GATEWAY:                            192.168.219.2
IP4.DNS[1]:                             192.168.219.2
IP4.DOMAIN[1]:                          localdomain
IP6.ADDRESS[1]:                         fe80::3442:365:1982:aa4b/64
IP6.GATEWAY:       

Configure commands

• Configure DNS: nmcli con mod test-lab ipv4.dns "8.8.8.8 8.8.4.4"
• Activate Ethernet connection: nmcli con up test-lab ifname ens9
• View details: nmcli -p con show test-lab
• Configure IP in eth0:

nmcli c add type ethernet ifname eth0 con-name "My_New_Connection" ip4 192.168.1.166/24 gw4 192.168.1.1
Connection "My_New_Connection"  (xxxxxxx-sdafasfsdf-adfasdfaf-adsfads) suceessfully added.

Activities

1. Configure network bonding using nmcli: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html-single/configuring_and_managing_networking/index#configuring-network-bonding-using-nmcli_Configuring-Networking-with-nmcli

See also

• Netplan: netplan try, netplan apply, examples, networkd
• NetworkManager, nmcli, /etc/NetworkManager/
• ip [link, route], ifconfig netstat ss lsof ping ethtool mii-tool arping nmcli(RHEL) route networkctl, netplan, tc

https://cgit.freedesktop.org/NetworkManager/NetworkManager/commit/?id=c2ec07f17d69a590b45797de5c8a0f26a4c45eaa