Components of the Series 925 Through Series 949 Systems

Figure 12-4 Large and Small Cabinet Installations

• The SPU houses system cards (memory, peripheral, processor) and the power supply.

• The battery backup unit (BBU) supplies power to memory cards in the event of a power failure.

• The CIO expander provides eight additional peripheral card slots to the SPU.

• The disk drive is a nonremovable drive used to store data. Other disk drive models are supported. Several disk drives can be connected to the system.

• The tape drive is used initially to load the operating system. Several tape drives can be connected to the system.

• The operating system resides on the system disk once it has been installed.

• The system console is the terminal device designated to send and receive system messages.

• Several types of page printers and line printers can be connected to the system.

Switches and Lights on Series 925 Through Series 949 Systems

As system manager, you may need to turn off the computer system or report system status to a Hewlett-Packard support representative when there is a system problem. The large cabinet shown in Figure 12-5 “Series 925 through Series 949 Switches and Lights” has a power breaker switch in the rear. Use the switch to turn on and off the SPU and all of the peripherals connected to the power outlet inside the cabinet. The small cabinet has no power outlet inside the cabinet, so you turn off each unit with its own on and off switch.

Figure 12-5 Series 925 through Series 949 Switches and Lights

The same system status panel is on the front of both the large and small cabinets and is shown in Figure 12-6 “Series 925 through Series 949 System Status Panel”. It is used to view system status and to enable remote access.

Figure 12-6 Series 925 through Series 949 System Status Panel

Viewing inside the panel, you see the following:

To remove the SPU Card Cage

The SPU card cage must be removed from the SPU before you can view the cards. The system manager never needs to do this because Hewlett-Packard support representatives normally remove the card cage to service the system.

To understand the CIO expander

The channel input/output (CIO) expander is supported on Series 925 through Series 949 systems but not on Series 950 through Series 980 systems. As a system manager, you never have to access the inside of the CIO expander. This is done by Hewlett-Packard support representatives only; however, it is important to be familiar with what type of cards the CIO expander supports when you are configuring your system.

The CIO expander provides eight additional (five supported) CIO card slots to the SPU. The CIO card slots house the network, console, and device adapter cards. These CIO cards are used to communicate between the SPU and either networks, system consoles and remote consoles, or various peripherals.

Figure 12-7 Series 925 through Series 949 CIO Expander

The CIO expander is connected with a cable to the processor-dependent hardware (PDH) card on the Series 935 system and to a channel adapter card on the Series 925 system.

CIO expander status lights

The status lights are on the front of the CIO expander, as shown in Figure 12-7 “Series 925 through Series 949 CIO Expander”. The ON/STANDBY button is used to turn the CIO expander on and off. The FAULT light and the RUN light indicate the following:

• The red FAULT light indicates that a fault condition has occurred.

• The green RUN light shows that the CIO expander is running.

	NOTE: If the red FAULT light goes on (the green RUN light goes off), call Hewlett-Packard support personnel and report what the status lights are displaying on the system status panel.

To understand the battery backup unit

There are two kinds of secondary power supplies supported on Series 900 computer systems:

The battery backup unit (BBU) is supported on Series 925 through Series 949 systems but not on Series 950 through Series 980 systems because they already have a system-installed battery. The BBU provides power to the memory cards for at least 15 to 25 minutes in the event of a power outage. By knowing how to read the front panel, you can determine if the system is running on the battery. The two lights on the front panel of the BBU, in combination with the FAULT light on the SPU, give status about the BBU. Figure 12-8 “BBU Status Lights” shows the BBU status lights. Table 12-3 “BBU Status Lights” provides BBU status information.

Figure 12-8 BBU Status Lights

Battery status conditions are described as follows:

When the BBU is providing power to the memory cards, the BATTERY light is on. In this state, the system is not available for command input. When power returns to the system, the AC ON light comes on. If the BATTERY light is still on, the BBU is still charging. The system resets and does not clear memory. This condition is known as a return from power fail. As power returns to the system after the BBU has returned to standby condition, the system resets and clears memory.