RHCSA Rapid Track

Use the systemctl status command to determine the status of system daemons and network services started by systemd.

The systemctl list-dependencies command lists all service units upon which a specific service unit depends.

systemctl reboot and systemctl poweroff reboot and power down a system, respectively.

systemctl isolate desired.target switches to a new target at runtime.

systemctl get-default and systemctl set-default can be used to query and set the default target.

Use rd.break on the kernel command-line to interrupt the boot process before control is handed over from the initramfs. The root file system is mounted read-only under /sysroot.

The emergency.target target can be used to diagnose and fix file system issues.