Fact:

• 3COM ONLY - DO NOT DISTRIBUTE THIS SOLUTION OUTSIDE
• CoreBuilder 3500
• 3C35004, CB3500 System Processor Module
• 3C35100, CB3500 Chassis
• Resue Boot PCMCIA card

Symptom:

• Corrupted software
• Device fails to boot
• Chassis fails to boot
• Fails to boot
• Corrupted sysboot software
• Error: "Missing: no valid sysboot file"

Fix:

The system can be recovered with a PCMCIA card with a special

"ELF" image. This is also known as a "Rescue Boot Card". See
description below.
Rescue Boot Card

What is a Rescue Boot Card?

On occasion, the apBoot code in flash gets corrupted. We have code in the software upgrade path to prevent this from happening, but people do not always use the standard mechanisms. In the past, when this happened, we had to take the processor board to someone in the hardware group who would hook the board up to a flash programming device and re-program the flash device with the boot code.

There's a better way! POV has a mechanism that will allow it to boot directly from a PCMCIA card if the card contains a valid ELF image. ELF is a standard format for executable images and it's the format of our apBoot and operational images before we place image headers on them. I have created this PCMCIA card that contains a apBoot image in the first few sectors of the card that does not have an image header on the front of it. This image can therefore be run by POV even if the apBoot image in flash has been corrupted. This apBoot image has a mechanism for installing images to flash, so it can then be used to restore the system.

— David Gonzalez 2021/04/13 16:34