Signal only the service main process.
Section: systemd Service Control
Signal only main PID
bash
bash
sudo systemctl kill --kill-whom=main -s SIGUSR1 nginxExplanation
Signal only the service main process.
Learn the surrounding workflow
Compare similar commands or jump into common fixes when this command is part of a bigger troubleshooting path.
Related commands
Same sheet · prioritizing systemd Service Control
Send signal to service cgroup
Signal all or selected processes in a service cgroup.
Reload or restart if reload unsupported
Use reload when available, else restart.