Resetting the System

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.

	NOTE: You can also initiate soft resets on the Series 922 through Series 949 systems by using the front panel RESET switch, which is described 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. Using the front panel RESET switch on the Series 950 through Series 980 systems, shown in figure 2-2, also performs a hard reset; however, you should use this switch for a hard reset only if the RS command fails. (The RESET switch on the Series 922 through Series 949 systems, shown in figure 2-1, initiates a soft reset.)

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

Resetting the system using the console

The console interfaces with the 900 Series HP 3000 through the access port (AP) located in the channel I/O (CIO) section of the system card cage. In addition to providing other features and commands, the AP allows 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 AP command. It responds to 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 “AP Reset Commands”.

Refer to Appendix A “Using the Access Port (AP)” for details about using the AP support interface for functions other than resetting the system.

To reset the system using the access port (AP), follow the directions listed below:

If you have a 9X8LX or 9X8RX system, a PDC menu is displayed when you issue CTRL B. From that menu, you can proceed to boot your system by typing BO. No specific reset is required.

Example 2-1 demonstrates a soft reset of the system with autoboot disabled using the console and AP commands for a Series 949 system. The reset screen may a contain different boot path and additional information, depending on the system you are using.

   CM> TC



   Processor Dependent Code (PDC) revision 2.2



   Console Path        = 4.2.0.0.0.0.0

   Primary boot path   = 4.1.0.0.0.0.0

   Alternate boot path = 4.5.0.0.0.0.0



   Boot from primary boot path (Y or N)?>

Answering NO to the boot path prompt initiates other prompts that query for the proper path to the boot device. If you answer YES to the primary path prompt, the system displays additional messages as it boots the processor and operating system.

Example 2-2 demonstrates a soft reset of the system with autoboot enabled, using console and AP commands for a Series 949 system. The reset screen may contain a different boot path display and additional information, depending on the system you are using.

	NOTE: If you have a 99X system, you must transfer to the service processor before you reset the system. CM> SP If you have a 9X8LX or 9X8RX system, you need to type BO to boot the system from the primary path.

   CM> TC





   Processor Dependent Code (PDC) revision 3.2



   Console Path        = 4.2.0.0.0.0.0

   Primary boot path   = 4.1.0.0.0.0.0

   Alternate boot path = 4.5.0.0.0.0.0





   Autoboot from primary path enabled.

   To override, press any key within 10 seconds.

If you do not press a key to interrupt the sequence, the system displays messages as it automatically boots the processor and operating system.

The autoboot flag setting determines whether the system searches for an autoexecute file with which to boot the operating system automatically.

	NOTE: If an autobooting system cannot locate a valid autoexecute file, it boots to ISL; therefore, you see the statement Cannot find an autoexecute file. AUTOBOOT ABORTED. This does not present any problems; just continue with the START command in ISL.

Resetting the system with the front panel switches

As indicated above, it is recommended that hard resets be done from the console rather than from the RESET switch whenever possible. The following information discusses using the RESET buttons.

The reset switch (a lock labeled "ENABLED, SECURED, and RESET") for the Series 922 through Series 949 systems is located behind the cover on the right end of the access panel. Figure 2-1 indicates the location of the switch on these systems.

Figure 2-1 Location of Series 922 through Series 949 Systems Reset Switch

The reset button (a gray button marked Reset) for the Series 950 through 980 systems is located underneath the cover of the horizontal portion of the system control panel. Figure 2-2 indicates the location of this button on these systems.

Figure 2-2 Location of Series 950 through Series 980 Systems Reset Button

	CAUTION: Pressing the reset button on Series 950 through 980 systems initiates a hard reset. Hard resets are disruptive resets that terminate all I/O operations and reset system memory. For this reason, reset Series 950 through Series 980 systems with the reset button only when other attempts to clear system failures have failed or when the data in memory and I/O processes are expendable. Do not use the reset button to reset Series 950 through Series 980 systems for a dump. Resetting these systems with the reset button invalidates dump data.

Pressing the reset button on Series 950 through Series 980 systems initiates a hard reset.

Resetting Series 922 through Series 949 systems by placing the key in the reset switch and turning the key to RESET initiates a soft reset.

The system responds by self-testing its components and issuing messages. Example 2-3 demonstrates the messages received at the consoles of a Series 949 system. The reset screen may contain a different boot path display and additional information, depending on the system you are using.

   Processor Dependent Code (PDC) revision 2.9



   Console Path        = 4.2.0.0.0.0.0

   Primary boot path   = 4.1.0.0.0.0.0

   Alternate boot path = 4.5.0.0.0.0.0



   Enter boot path, command, or ?>

	NOTE: Disabling and enabling autoboot is explained in Chapter 3 “System Startup Functions”.

Answering NO to the boot path prompt initiates other prompts that query for the proper path to the boot device. If you answer YES to the primary path prompt, the system displays additional messages as it boots the processor and operating system. (Information on appropriate boot paths is provided later in this chapter.)

The messages received after a system is reset depend on whether autoboot is enabled. Recall that autoboot describes the system's capability to boot itself (without operator intervention) after it has been reset. Messages from a system with autoboot enabled differ from the messages received at a system with autoboot disabled. Example 2-4 demonstrates the messages received from a Series 949 system.

   Processor Dependent Code (PDC) revision 2.9



   Console Path        = 4.2.0.0.0.0.0

   Primary boot path   = 4.1.0.0.0.0.0

   Alternate boot path = 4.5.0.0.0.0.0



   Autoboot from primary path enabled.

   To override, press any key within 10 seconds.

If you do not press a key to interrupt the autoboot sequence, the system displays messages as it automatically boots the processor and the operating system.