Booting BIOS Flash images via iPXE

[cpdohert]

I have several BIOS Flash floppy images that work fine with syslinux 4.0 and memdisk. They are all FreeDOS boot floppy images created using the method described here.

Because the BIOS images are larger than 2.88 MB, I can't use a regular FreeDOS boot image. That's why I created disk images from scratch of the size I need.

The problem I've got now is that none of the images will boot with a sanboot command in iPXE. Using the following command:

Code:

iPXE> sanboot --no-describe --drive 0x00 http://ipxe.internal.url/8440w/8440w.img

returns:

Code:

Registered SAN device 0x00
Booting from SAN device 0x00
FreeDOS

And then it hangs there forever. By contrast, the official FreeDOS boot floppies and the dosboot.img image iPXE links to in the "Updating with a Custom ROM" section boot just fine.

I have also tried --drive 0x80 with the same result.

So clearly there's a problem with my custom floppy images, but I don't know why they aren't working. What exactly has to be true for a sanboot target to boot correctly?