Which systemd-based command powers off the system?

• A. poweroff
• B. systemctl poweroff
• C. shutdown -P
• D. halt

Answer: (B)

When using systemd, powering off the machine is done with the systemctl poweroff command. This explicitly asks systemd to run the shutdown sequence and reach the poweroff.target, ensuring all units and services are stopped cleanly, filesystems unmounted, and the hardware is then powered down. It’s the formal, systemd-native way to shut down.

Other options may also halt or power off in some environments, but they aren’t the explicit systemd interface. A plain poweroff command can be a wrapper or link to systemctl in some distros, shutdown -P is a traditional shutdown utility that can power off, and halt may stop the system without necessarily powering the hardware off, depending on the setup.