On Mon, May 25, 2020 at 05:19:23PM +0000, Mogens Jensen wrote:
On Friday, May 15, 2020 2:17 AM, Kevin O'Connor kevin@koconnor.net wrote:
On Tue, May 12, 2020 at 03:39:58PM +0000, Mogens Jensen wrote:
I would expect that it should not matter that flash disk is inserted in USB port, as long as no boot sector is present on the device. If this is NOT correct behaviour, then what could be the problem here?
Although that expectation is reasonable, it's not how a traditional BIOS works. One can select which hard drive is the "bootable" drive during the "boot menu" phase. That drive effectively becomes the "C:" drive and it can be booted from. However, if that drive is not bootable then no hard drive can be booted (as in practice it's only possible to boot from the "C:" drive on a BIOS).
So, in short, use the boot menu to select the alternate drive (or the bootorder cbfs file). Don't expect an automatic search of bootable harddrives.
I did a test with QEMU emulator version 4.2.0, which is using SeaBIOS. Hard disk is configured as first boot device, but has no boot sector:
=== Booting from Hard Disk... Boot failed: not a bootable disk
Booting from Floppy... Boot failed: could not read the boot disk
Booting from DVD/CD...
QEMU will then correctly boot the CD ISO image. This is EXACTLY the behaviour I'm looking for.
Can I configure coreboot/SeaBIOS so booting works in the same way on my system?
Certainly. SeaBIOS supports booting from floppy or cdrom on a failure to boot from a harddrive (as do traditional bios). Your original query was on booting from a different harddrive, and that isn't something that a traditional bios (nor SeaBIOS) supports.
-Kevin