Dan Nelson dnelson at allantgroup.com
Tue Mar 30 15:17:10 UTC 2010

In the last episode (Mar 30), Fbsd1 said:
> During the boot process I want to change the device used to boot from.
>  From the default 0:ad(0,a)/boot/loader
> to 0:da(0,a)/boot/loader forcing the boot to continue from usb stick.
> Here is the problem, the bios have no option to boot from USB device.  So
> thinking let the bios point to first drive to start the boot process and
> have a /boot.config file to redirect to booting from the USB stick.  I am
> assuming the '0' zero will mean the first USB device.
> Is there any command i can use to verify the single USB stick is the 0 
> device?

If you boot DOS from a floppy, can you see the USB stick as B: or C: ?  If
not, then the BIOS probably has no USB support at all, and you'll need to
put a small boot partition somewhere on your hard drive to pull the kernel
from.  128MB is large enough for a /boot directory, and you can set
vfs.root.mountfrom="ufs:/dev/da0s1a" in loader.conf to make it mount its
root filesystem from the USB stick (since at that point the kernel has
loaded its own USB drivers).

If you do see the USB drive from a DOS boot floppy, try entering
"1:da(0,a)?" at the boot block prompt and see if it lists the files in your
USB filesystem.  If it does, then "1:da(0,a)/boot/loader" should let you
boot FreeBSD.

	Dan Nelson
	dnelson at allantgroup.com

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