Fbsd1 fbsd1 at a1poweruser.com
Wed Mar 31 03:53:44 UTC 2010

Dan Nelson wrote:
> 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.

The USB stick is plugged in before booting. During boot I select option 
6 from Freebsd menu to go direct to the loader prompt. I have ok on 
command line. I enter
  vfs.root.mountfrom="ufs:/dev/da0s1a" and get "not found" after hitting 
enter key.
At the ok prompt I enter ? for list of available boot devices and only 
have ad0 listed.

It seems the da0 device USB stick is not recognized yet.

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