In the following example, the shutdown is used to bring a SPARC based system to run level S (single-user state) in 3 minutes.
# who root console Jul 14 13:53 # shutdown -g180 -y Shutdown started. Wed Jul 14 13:55:55 MDT 1999 Broadcast Message from root (console) on earth Wed Jul 14 13:55:56... The system earth will be shut down in 3 minutes . . . Broadcast Message from root (console) on earth Wed Jul 14 13:58:28... The system earth will be shut down in 30 seconds . . . INIT: New run level: S The system is coming down for administration. Please wait. Unmounting remote filesystems: /vol nfs done. Jul 14 13:59:15 earth /usr/sbin/vold: problem unmounting /vol; Print services stopped. Jul 14 13:59:16 earth syslogd: going down on signal 15 Killing user processes: done. INIT: SINGLE USER MODE Type control-d to proceed with normal startup, (or give root password for system maintenance): xxx Entering System Maintenance Mode ... #