# Turning on 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. First, 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/ Second, 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 You must reload the systemctl daemon and restart the systemd-networkd service for the changes to take effect: systemctl daemon-reload systemctl restart systemd-networkd Verify that your changes took effect: systemd-delta --type=extended View the log files by running this command: journalctl -u systemd-networkd When you are finished 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