Booting After Adding New Hardware

When you add new hardware to your system, you must use the -r option to the boot command so that the operating system knows to look for new device drivers and incorporate them as part of the boot process:

1.  Load the new device driver, following the instructions included with the hardware.

2.  Shut down your system and install the new hardware.

3.  Type boot -r and press Return. A reconfiguration script is run to load all the device drivers listed in the modules directories and to create the corresponding hardware nodes.

Aborting a Booting Process

Occasionally, you may need to abort the booting process. The specific abort key sequence depends on your keyboard type. For example, you might press Stop-A or L1-A. On tty terminals, press the Break key.

To abort the booting process, type the abort key sequence for your system. When you abort the boot process, the monitor displays the ok PROM prompt:

ok

Type boot and press Return to restart the boot process, or type help and press Return to display a list of help options. If your terminal shows the > monitor prompt, type n to get the ok prompt.

Shutting Down a System

The following sections describe how to use the shutdown and init commands to shut down a system.

Shutting Down a Multiuser System

Before shutting down a multiuser system, inform the other users on the system and give them time to complete critical procedures such as saving changes:

1.  Type who and press Return. A list of all logged in users is displayed.

2.  Type ps -ef and press Return. A list of system activities is displayed. If the activity is acceptable for running shutdown, go to the next step.

3.  Become superuser.

4.  Type cd / and press Return. You must be in the root directory to run the shutdown command.

5.  Type shutdown and press Return. You are asked to confirm that you want to shut down the system.

6.  Type y. A message is broadcast to all users. After a 60-second wait, the system is shut down to single-user state and you are prompted for the root password.

7.  Type the root password. The system is in single-user state and you can perform any maintenance task.

8.  Press Control-D to return to the default run system level:

# cd /
# shutdown
Shutdown started Fri Aug 6 1Ø:5Ø:35 EDT 1993

Broadcast message from root (console) on earth Fri Aug 9 1Ø:59:35.
THE SYSTEM IS BEING SHUT DOWN NOW ! ! !
LOG OFF NOW OR RISK YOUR FILES BEING DAMAGED
Do you want to continue?  (y or n):  y

The system is down.
Changing to init state s - please wait.

INIT: New run level S
INIT: SINGLE USER MODE
Type Ctrl-d to proceed with normal start-up,
(or give root password for system maintenance):

Shutting Down a System: Alternative Ways

If you want to change the default actions of the shutdown command, choose one of the tasks in the following six sections.

Shutting Down a System Without Confirmation

To shut down a system without confirmation, follow these steps:

1.  Become superuser.

2.  Type cd / and press Return. You must be in the root directory to run the shutdown command.

3.  Type shutdown -y and press Return. The shutdown proceeds without asking you to type y to confirm it.

Changing the Shutdown Grace Period The default is for the shutdown command to provide a 60-second grace period to enable users to save their changes. To change the shutdown 60-second grace period, follow these steps:

1.  Become superuser.

2.  Type cd / and press Return. You must be in the root directory to run the shutdown command.

3.  Type shutdown -g nnn and press Return. The grace period is changed to the number of seconds you specify.

The following example changes the grace period to 120 seconds:

# d /
# shutdown -g12Ø

Shutting Down and Rebooting a Multiuser System To shut down and reboot a multiuser system, follow these steps:

1.  Become superuser.

2.  Type cd / and press Return. You must be in the root directory to run the shutdown command.

3.  Type shutdown -i6 and press Return. A message is broadcast to all users and the rc script is executed; the system is shut down to power-down state and then brought back up to multiuser state.

Shutting Down a Single - User System To shut down a single-user system, type telinit 0 (or init 0) and press Return. The init command runs scripts that bring the system down cleanly. No warning messages are broadcast.

Shutting Down and Rebooting a Single - User System To shut down and reboot a single-user system, type telinit 6 (or init 6 ) and press Return. Information is written to the disk, all active processes are killed, and the system is brought to a power-down state. The system is then rebooted to the default level (usually multiuser).

Shutting Down a System in a Hurry To shut down a system in a hurry, type uadmin 2 0 and press Return. Information is written to the disk and the system is brought to power-down state, displaying the PROM prompt.

Monitoring Processes

The programs that are running on a system at any one time are called processes. You can monitor the status of processes, control how much CPU time a process gets, and suspend or halt the execution of a process.