yawetaG wrote:That sounds like the generic BIOS "drive letter" selection for IDE drives that some BIOSes have. The drive letters shown (confus […]
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SirNickity wrote:The BIOS boot order is pretty lame. You get a drive lettering priority of IDE or SCSI. Then you get to choose from a list of device orders: A, C; A, CDROM, C; CDROM, C, A; LS/ZIP, C; D; E; C only, etc.
That sounds like the generic BIOS "drive letter" selection for IDE drives that some BIOSes have. The drive letters shown (confusingly) do not correspond to your logical drive letters.
The computer BIOS (not the Adaptec BIOS) needs to explicitly support SCSI booting (e.g. it reads "SCSI" in one of the options). The Adaptec SCSI card's BIOS gets spliced into the boot sequence and will only allow booting from SCSI if the motherboard explicitly supports booting from SCSI, or if no alternative boot devices are present on the IDE bus.
Furthermore, if the motherboard does support booting from drives attached to a separate SCSI host adapter, there may be limitations regarding which adapters are supported (they will be listed in the motherboard manual).
Most motherboards will permit booting from a SCSI drive (or a network boot) even without an explicit SCSI or Network option.
All that is required is that the option card (SCSI or network) hooks INT18 at initialisation, and that the BIOS calls INT18 to "start cassette basic" when an attempt to boot each of the configured devices fails. Again, most bootable cards will do this, but only the last one to hook the interrupt will get a bite of the cherry.
If I were in the OP's position I would:
Option A
Temporarily install an IDE CD drive, and have done with all these shenanigans, boot from CD, run GRUB, get a beer.
Option B
1) Follow the earlier advice to see if it is possible to boot from a CD which has an emulated floppy image
If that works, and bearing in mind the objective: boot the system and re-run GRUB (and assuming Linux)
2) Create a bootable CD with an emulated floppy containing a bootable stripped down kernel and an initrd or maybe even just a plain kernel image.
The floppy would either be configured to use the hard disc root partition as root, or would use a bootloader which allowed me to tell it which partition to use.
Note that "stripped down" means absolutely nothing beyond that required to get the root partition to mount and get me to a login prompt.
Any boot time errors regarding non-essential hardware can be ignored - you want to get the root partition mounted so you can run GRUB.
You will need to know how to configure and compile a kernel, and create an initrd.
This option has dependencies on your hardware:
1) Can your system actually boot a el-torito CD with an emulated floppy?
2) The emulated floppy will have to be 2.88Mb - you would be hard pressed to get a x86 kernel small enough to fit within 1.44Mb
Can your system handle a 2.88Mb floppy image?
The fact that it can recognise a bootable CD, doesn't mean it can actually boot it. (I can drive a car, and recognise a fire truck, it doesn't mean that I can drive a fire truck)
