Solaris 7 Sun Hardware Platform Guide

Scenario 2--System Does Not Recover After Power Restoration

If your system does not boot, run diagnostics, or return to the PROM monitor's ok prompt after power is restored, complete the following steps:

  1. If the update was being run via a serial port and the system also has a frame buffer and keyboard installed, or if the system has a keyboard and more than one frame buffer installed:

    1. Connect a monitor to each frame buffer.

    2. Confirm that output has been redirected to one of the frame buffers.

      • The NVRAM configuration variables might have been modified because of the firmware update just before power was lost. If this happened, then the system output was possibly redirected to a device other than the one originally used to display it. This could only have happened if a keyboard was connected to the system.

      • If there is no keyboard connected to the system and the NVRAM configuration variables are set to their default values, then system input and output are directed to serial port A.

  2. If output cannot be found on any of the installed frame buffers or serial port A, set the boot control jumper to boot from the half of the PROM that is not currently selected. See Figure 4-1 Figure 4-2, Figure 4-3, Figure 4-7, and Figure 4-8. An asterisk (*) on the main logic board notes the location of pin 1.

    • If the jumper is set for high-half booting, move it to low-half booting (pins 2 and 3 jumpered). See Figure 4-7.

    • If the jumper is set for low-half booting, move it to high-half booting (pins 1 and 2 jumpered). See Figure 4-7.

    Table 4-5 Boot Control Jumper



    Pins 1 + 2 Jumpered 

    Pins 2 + 3 Jumpered 

    Default Jumper on Pins 


    Ultra 1, 2 


    High-half booting 

    Low-half booting 

    2 + 3 

    Boot control 

    Sun Enterprise 450 or Sun Ultra 450 workstation 


    High-half booting 

    Low-half booting 

    2 + 3 

    Boot control 

    Figure 4-7 Setting the Boot Control Jumper to Low-Half Booting or High-Half Booting


  3. Power on the system unit.

    • If the system does not recover, repeat Step 1 and Step 2 a second time.

  4. If the system still does not recover, contact your Sun service provider or local Sun service Authorized Service Provider.