Planning a Reliable Configuration

Using an Uninterruptible Power Supply

An uninterruptible power supply (UPS) provides constant power to a computer system when a power fluctuation or power loss occurs. Built-in electronics constantly monitor line voltages: if the line voltage fluctuates above or below predefined limits, or fails entirely, the UPS supplies power to the computer system from built-in batteries. The UPS converts the direct current (DC) battery voltage into the alternating current (AC) voltage required by the computer system. The change to batteries must take place very rapidly to prevent data loss.

Most UPS devices are one of the following types:

Online UPS. An online UPS is connected between the main power and the computer that constantly supplies power to your computer. The main power continuously charges the batteries which supply the power to the computer. Connecting it to the main power keeps its battery charged. This method provides power conditioning, which means that it removes spikes, surges, sags, and noise.
Standby UPS. A device configured to provide either the main power or its own power source and to switch from one to the other as necessary. When main power is available, the UPS device connects the main power directly to the computer and monitors the main power voltage level. When the main power fails or the voltage falls below an acceptable level, the UPS device switches to its own power.

Use only UPS hardware that is included on the Windows 2000 HCL. Other options to consider include:

Whether to use a separate UPS for each computer or have larger capacity, centralized UPSs that protect multiple computers.
What type of UPS you want to use.
How big the UPS needs to be to protect your computer systems.
How long the UPS needs to run before automatically shutting down.
What other features your UPS needs to have, such as:
- Continuous conditioning of the incoming power to provide clean, steady power.
- Software that produces statistics or logs UPS information to the event log.
- Software for testing the integrity and reliability of the UPS battery.

For robust resistance to power failures, use UPS hardware connected to the computer and software that handles power failures, including shutting down the system before the UPS batteries are depleted. Without such software, human intervention is needed to shut down the system.

Windows 2000 has built-in UPS functionality that takes advantage of the features included with many UPS systems, such as ensuring the integrity of data on the system by providing for an orderly shutdown of the computer system if a power failure lasts long enough to deplete the UPS batteries. In addition, users connected to a computer running Windows 2000 Server can be notified that a shutdown will occur, and new users are prevented from connecting. Finally, damage to the hardware from a sudden, uncontrolled shutdown can be prevented.

Some vendors also provide a user interface for configuring the UPS, which you can use instead of the one provided in Windows 2000.

To fully protect your network, you also need to install a UPS on network devices such as routers, hubs, and bridges. For the best protection, install UPS systems on the cables that connect your computer to your modem, telephone, printer, and network equipment. Most UPS systems have built-in surge protection.

In Control Panel, click Power Options to configure the Windows 2000 UPS service.

To configure the UPS service in Windows 2000

In Control Panel, select the Power Options option.
Select the UPS tab, and then click the Select button.
From the UPS Select dialog box, select the manufacturer and model of the UPS unit you are using.
In the On port field, select the port to which the UPS is connected, and then click Finish.
On the UPS page of the Power Options Properties dialog box, click the Configure button.
From the UPS Configuration dialog box, select the configuration options that best suit your needs.
Click OK.
On the UPS page of the Power Options Properties dialog box, click OK or Apply to commit the new settings.

The remaining information depends upon your specific UPS and its use.

When selecting the signals to use in the UPS Configuration group box, the interface voltages indicate the active state for the signal. For example, if you select a negative interface voltage for the power failure signal, the normally positive signal becomes negative when a power failure occurs.

Use the following procedure to configure the Windows 2000 UPS service to run a command file when a power failure occurs.

To configure the UPS service in Windows 2000 to run a command file when a power failure occurs

In the UPS Configuration dialog box, select the When the alarm occurs, run this program check box, and then click Configure.
In the UPS System Shutdown Program dialog box, select the Task tab.
Type the name of the file in the Run field.
If you want the scheduled task to run at a specified time, select the Enabled (scheduled task runs at specified time) check box and continue this procedure.
Select the Schedule tab, and then select the frequency and start time of the task.
For further schedule settings, click the Settings tab.
Choose from options in the Scheduled Task Completed, Idle Time and Power Management areas of the Settings tab, then click OK.
In the Set Account Information dialog box, type the Run as and password information, and then click OK.

Note

The command file must reside in %SystemRoot%\System32 and have a file name extension such as .exe, .com, .bat, or .cmd.