Mastering nmcli: Essential Commands to Manage Linux Network Interfaces

Common nmcli Commands

nmcli connection show

Display detailed information for all network connections. nmcli connection up <UUID|NAME> Activate the specified connection (identified by UUID or connection name). nmcli connection down <UUID|NAME> Deactivate the specified connection.

nmcli connection modify <UUID|NAME> ipv4.addresses <IP>/<netmask>

Set a static IPv4 address. netmask is the CIDR prefix length (e.g., 24 for 255.255.255.0 ).

nmcli connection modify <UUID|NAME> ipv4.gateway <gateway>

Define the IPv4 default gateway.

nmcli connection modify <UUID|NAME> ipv4.method manual

Switch the IPv4 method to manual (required for static addressing).

nmcli connection modify <UUID|NAME> ipv6.addresses <IP>/<netmask>

Set a static IPv6 address (CIDR notation).

nmcli connection modify <UUID|NAME> ipv6.gateway <gateway>

Define the IPv6 default gateway.

nmcli connection modify <UUID|NAME> ipv6.method manual

Switch the IPv6 method to manual.

nmcli connection modify <UUID|NAME> dns <DNS server>

Set DNS server(s) for the connection (comma‑separated for multiple servers).

nmcli connection modify <UUID|NAME> mtu <MTU value>

Adjust the Maximum Transmission Unit. nmcli connection show --active List all currently active connections. nmcli connection delete <UUID|NAME> Remove a connection profile.

Rename a Network Interface

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

Add a New Interface

nmcli connection add type ethernet con-name ens37 ifname ens37

Activate or Deactivate an Interface

# Reload connection definitions (useful after editing files)
nmcli connection reload

# Bring the interface up
nmcli connection up ens33

# Bring the interface down
nmcli connection down ens33

# Restart the interface (down then up)
nmcli connection down ens33 && nmcli connection up ens33

Configure a Static IP Address

Set a fixed IPv4 address, gateway, and DNS for a specific interface.

# Replace placeholders with actual values
nmcli connection modify <interface|UUID> \
    ipv4.method manual \
    ipv4.addresses <IP>/<netmask> \
    ipv4.gateway <gateway> \
    ipv4.dns <DNS server>

# Example for interface <strong>ens37</strong>
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

# Apply the changes by restarting the interface
nmcli connection down ens37 && nmcli connection up ens37

# Verify the configuration
nmcli connection show ens37

Switch an Interface to DHCP

Remove any static IPv4 configuration and let the interface obtain its address automatically.

# Clear static IPv4 settings (empty strings remove the values)
nmcli connection modify ens37 ipv4.addresses "" ipv4.gateway "" ipv4.dns ""

# Change the method to automatic (DHCP)
nmcli connection modify ens37 ipv4.method auto

# Restart the interface to request a DHCP lease
nmcli connection down ens37 && nmcli connection up ens37