Mastering nmcli: Essential Commands to Manage Linux Network Interfaces

Below are some common nmcli command options and usage:

connection show               # Show detailed information of all network connections
connection up <UUID>            # Activate a network connection
connection down <UUID>          # Deactivate a network connection
connection modify <UUID> ipv4.addresses <IP>/<netmask>   # Change IPv4 address
connection modify <UUID> ipv4.gateway <gateway>        # Change IPv4 gateway
connection modify <UUID> ipv4.method manual          # Set IPv4 method to manual
connection modify <UUID> ipv6.addresses <IP>/<netmask>   # Change IPv6 address
connection modify <UUID> ipv6.gateway <gateway>        # Change IPv6 gateway
connection modify <UUID> ipv6.method manual          # Set IPv6 method to manual
connection modify <UUID> dns <DNS server>            # Change DNS server
connection modify <UUID> mtu <MTU value>            # Change MTU value
connection show --active      # Show all active network connections
connection delete <UUID>      # Delete a network interface

1) Rename a network interface

nmcli c modify uuid f136e0e3-5faf-4d2f-8c5f-4ce976585b30 con-name ens33

2) Add a network interface

nmcli connection add type ethernet con-name ens37 ifname ens37

3) Activate or deactivate a network interface

nmcli connection reload                     # Reload interfaces
nmcli connection up ens33                   # Activate interface ens33
nmcli connection down ens33                 # Deactivate interface ens33
nmcli connection down ens33 && nmcli connection up ens33   # Restart interface ens33

4) Set static IP mode for an interface

Use nmcli to configure a static IP address.

nmcli connection modify <interface> ipv4.method manual ipv4.addresses <static_ip>/<netmask> ipv4.gateway <gateway_ip> ipv4.dns <dns_ip>

nmcli connection modify ens37 ipv4.method manual ipv4.addresses 192.168.70.133/24 ipv4.gateway 192.168.70.2 ipv4.dns 114.114.114.114
# Restart the interface to apply the configuration
nmcli c down ens37 && nmcli c up ens37
# View detailed information of the interface
nmcli connection show ens37

5) Switch an interface to DHCP mode

Set the eth0 interface to obtain an IP address via DHCP.

# Remove previously set static IP configuration
nmcli connection modify ens37 ipv4.addresses "" ipv4.gateway "" ipv4.dns ""
# Change the interface to DHCP mode
nmcli connection modify eth0 ipv4.method auto
# Restart the interface to apply changes
nmcli c down ens37 && nmcli c up ens37