# Network Debugging You can set `systemd-networkd` to work in debug mode so that you can analyze log files with debugging information to help troubleshoot networking problems. The following procedure turns on network debugging by adding a drop-in file in `/etc/systemd` to customize the default systemd configuration in `/usr/lib/systemd`. 1. Run the following command as root to create a directory with this exact name, including the `.d` extension: `mkdir -p /etc/systemd/system/systemd-networkd.service.d/` 1. Run the following command as root to establish a systemd drop-in unit with a debugging configuration for the network service: ``` cat > /etc/systemd/system/systemd-networkd.service.d/10-loglevel-debug.conf << "EOF" [Service] Environment=SYSTEMD_LOG_LEVEL=debug EOF ``` 1. Reload the `systemctl` daemon and restart the `systemd-networkd` service for the changes to take effect: ``` systemctl daemon-reload systemctl restart systemd-networkd ``` 1. Verify that your changes took effect: `systemd-delta --type=extended` 1. View the log files by running this command: `journalctl -u systemd-networkd` 1. After debugging the network connections, turn debugging off by deleting the drop-in file: `rm /etc/systemd/system/systemd-networkd.service.d/10-loglevel-debug.conf`