dig google.com
nslookup google.com
systemctl list-units
systemctl list-units --all
systemctl list-unit-files
journalctl
journalctl -b # Boot
journalctl -k # Kernel messages
journalctl -k -b # Current boot
journalctl -u nginx.service # Logs of specific service
journalctl -u nginx -f # Logs of specific service with follow
journalctl -u nginx.service --since "2023-10-01" --until "2023-10-02" # Logs of specific service in date range
journalctl -b -u nginx.service # Boot logs of specific service
systemctl list-dependencies nginx.service
systemctl list-dependencies --all nginx.service
sudo systemctl daemon-reload