Browse Prior Art Database

Boot Path Selection Verification and Override

IP.com Disclosure Number: IPCOM000123886D
Original Publication Date: 1999-Jun-01
Included in the Prior Art Database: 2005-Apr-05
Document File: 2 page(s) / 73K

Publishing Venue

IBM

Related People

Bealkowski, R: AUTHOR [+2]

Abstract

Disclosed is a method to verify and override, if required, a boot path selection. A boot source may be selected by the system but the operator may not want it booted in a specific case. The Boot Path Selection Verification and Override method eliminates the need to remove the media and reboot or change the stored boot sequence on a temporary basis.

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This is the abbreviated version, containing approximately 52% of the total text.

Boot Path Selection Verification and Override

   Disclosed is a method to verify and override, if required,
a boot path selection.  A boot source may be selected by the system
but the operator may not want it booted in a specific case.  The Boot
Path Selection Verification and Override method eliminates the need
to remove the media and reboot or change the stored boot sequence on
a temporary basis.

   A typical computer system has a programmable stored boot
sequence.  The default sequence is usually (1) diskette, (2) CD-ROM,
(3) disk, and (4) network.  The system will look for a bootable
device or bootable media (boot source) in the prescribed order,
selecting the first valid encounter as the boot device.

   The figure shows the Boot Path Selection Verification and
Override method.  Initialize search list determines the stored boot
sequence from system non-volatile random access memory (NVRAM) or
other non-volatile storage.  Next, locate next bootable media in boot
sequence scans forward in the list until a boot source is located.
Once a boot source is located, a check is made to determine if Boot
Path Selection Verification and Override has been set up in preferred
mode.  Preferred mode is where the system has a preferred boot
device, such as disk.  If the system is in preferred mode the
variable expected is set to the value of the preferred boot device.
If the system is not in preferred mode then it is in expected mode
and the expected variable is set to the previous boot device.
Expected mode is where the system expects to boot from the same
device...