System Startup, Configuration, and Shutdown Reference Manual (32650-90907)

Chapter 2

Initiating System Activity

Resetting the System

There are two general types of resets for the HP 3000 (Series 900): a soft reset and a hard reset.

Soft Reset

A soft reset, the type of reset used most often, preserves the current processor state. This type of reset

performs a nondisruptive memory test and terminates all I/O operations before executing recovery software

for starting the boot device and console selection process. A soft reset can also occur during a software reboot

at the completion of a bootable ISL utility, such as INSTALL, UPDATE, or DUMP.

More information on issuing resets from the console is provided later in this chapter.

Hard Reset

A hard reset is disruptive. It initiates the processor self-test that resets memory and terminates all I/O

operations. A hard reset is necessary after a hardware failure or after an error from which the system cannot

recover.

A hard reset is initiated when the CPU is powered on. If the system is powered on already, then entering the

reset command, RS, at the system console initiates the hard reset process.

More information on issuing resets from the console is provided later in this chapter.

Resetting the System Using the Console

With the release of the A and N-class systems, MPE supports two different types of access into the system

service ports. For NIO based systems, the console interfaces with the 900 Series HP e3000 through the access

port (AP) located in the channel I/O (CIO) section of the system card cage. For A and N-class systems, the

Guardian Service Processor (GSP) provides access through the core I/O card.

In addition to providing other features and commands, both the GSP and the AP allow the system manager or

system operator (OP capability) to issue hard or soft resets from the console keyboard instead of using the

front panel reset switch. (The system is secured from anyone accidentally entering an GSP/AP command. It

responds to GSP/AP commands only when the console is placed in control mode by entering

CTRL B.)

The access port supports two, two-character commands for resetting the system, as described in Table 2-1.

For NIO systems, refer to Appendix A for details about using the AP support interface for functions other

than resetting the system. For A and N class systems, refer to Appendix H for details about using the GSP

support interface for functions other that resetting the system.

Table 2-1 AP Reset Commands

Command Description

RS Reset SPU (hard reset). This command initiates a processor self-test that resets

memory and terminates all I/O operations. Do not use this type of reset in

preparation for a dump.

TC Transfer of control (soft reset). This command initiates a reset that preserves the

current processor state, terminates all I/O operations, and performs a

nondisruptive memory test.