Rebooting a running system

Because processes might be running that should be terminated more gracefully than a reboot permits, shutdown is the preferred method for all systems.

There are two methods for shutting down and rebooting your system, shutdown and reboot. Always use the shutdown method when multiple users are logged on to the system.
Task SMIT Fast Path Command or File
Rebooting a Multiuser System smit shutdown shutdown -r
Rebooting a Single-User System smit shutdown shutdown -r or reboot