A P P E N D I X  A

Power Management

This chapter discusses power management. Topics include:

A.1 Power Management Overview

To conserve power and to comply with the Energy Star program, mandated by US Environmental Protection Agency, the Sun Ultra 45 or Ultra 25 workstation power management features are enabled by default.

Note - The Sun Ultra 25 workstation meets or exceeds Energy Star guidelines in operation only when using the Javatrademark Desktop System (Java DS) windowing system, not while running the Common Desktop Environment (CDE) windowing system.

If you are currently using CDE, you can switch to the Java Desktop System by logging out from a CDE session, then logging back in after selecting Java Desktop System.

The Dtpower application reads and writes the Dtpower configuration to the /etc/power.conf file. You can change power management settings in the Dtpower application or you can make changes by editing the power.conf file. The Dtpower application is easier to use. Editing the power.conf file allows more control over power management than the Dtpower application provides.

This chapter provides some basic power management instructions. More detailed information is in the following documentation:




A.2 Using Dtpower

Dtpower has two preconfigured power management modes: minimal and standard. There is also a mode for customizing the settings. TABLE A-1 provides information about the different modes.

TABLE A-1 Dtpower Power Management Modes


Power Management


Only the displays go into low-power mode.


All devices go into low-power mode.


Allows user to customize settings for displays and disks.


No power management for any device.

Before you configure power management, consider the way that you use the Sun Ultra 45 or Ultra 25 workstation. For example: is the workstation used as a server? If so, use only minimal power management, or none at all.

The power.conf application provides greater controls on power management, such as managing multiple disk drives and other devices. For more information see the power.conf (1M) man pages.

A.3 Modifying Power Management

1. Open a terminal window and type the following command:

% dtpower &

The Dtpower window is displayed.

2. From the Current Power Saving Scheme pulldown menu, select Customized, Minimal, or Standard.

The application exits and you are finished.

The window expands. Continue with the remaining steps.

3. Select the Device Idle Time Before Power Saving Starts time.

For Example:

"15 Min" means that after 15 minutes of inactivity, all power-managed devices will go to low-power mode. "Always On" disables power management for the selected device.

4. Set the Override Device Idle Time for displays or drives.

5. Click OK to close the application.

A.3.1 Activating the Workstation From Low-Power Mode

If all devices are in low-power mode, the green LED on the front panel flashes. If any single device is powered up, the LED will stop flashing.

To reactivate the Sun Ultra 45 or Ultra 25 workstation from low-power mode, press the spacebar on the keyboard or move the mouse. If you are connected remotely, any system activity that you initiate can bring the workstation out of low-power mode.