How to use the command 'nmcli monitor' (with examples)

The ’nmcli monitor’ command is used to monitor changes to the NetworkManager connection status. It provides an efficient way to track any changes in the network configuration and allows users to take appropriate actions based on those changes.

Use case 1: Start monitoring NetworkManager changes

Code:

nmcli monitor

Motivation: Starting the network monitoring allows users to capture real-time updates regarding network connections and configurations. This is especially useful in scenarios where there might be frequent changes in the network environment, such as in a dynamic network environment or when troubleshooting networking issues.

Explanation:

• ’nmcli’ is the command-line tool used to interact with NetworkManager.
• ‘monitor’ is the subcommand that initiates the monitoring of NetworkManager changes.

Example Output:

Monitor: running... (press CTRL+C to quit)
Apr 23 15:30:14 NetworkManager[1234]: <info>  [1656090614.123456] Device 'eth0' state changed to disconnected
Apr 23 15:30:17 NetworkManager[1234]: <info>  [1656090617.123456] Device 'eth0' state changed to connected

In the example output, the monitoring is in progress and network events are being displayed. It shows that the ’eth0’ device state changed from disconnected to connected at respective timestamps.