Re: Official way of enabling USB on grub 2.02?

[Andrei Borzenkov]

В Fri, 09 Jan 2015 02:45:40 +0100
adrian15 <address@hidden> пишет:

> I'm having problems using my old commands (from grub 2.00) for enabling 
> USB when using grub 2.02. I also think that in grub 2.00 they did not 
> work completely ok.
> 
> Anyways, the question is:
> 
>    How one is supposed to enable Grub2's USB support when using: 2.02?
> 
> I'm currently doing my tests with Debian Jessie: 2.02~beta2-19 version.
> 
> 
> 
> These were the original commands:
>      insmod ohci
>      insmod uhci
>      insmod usbms
>      update_paths
> 
> The first one says:
> error: disk `hd96' not found
> 

USB drivers work with hardware directly and so conflict with BIOS
for hardware access. For this reasons as soon as you load any driver
that does it grub will stop calling into BIOS. As by default grub is
using BIOS for hard drive access, those devices no more work.

> and I cannot longer use my custom grub menues (The Super Grub2 Disk menus).
> 
> Thank you for any clue on how to enable USB support in the correct way.
> 

grub2 has command "nativedisk" that will try to switch from platform
firmware driver (BIOS) to native hardware disk drivers. This may give
you back your disks, but under different names. Note that some commands
will not function, e.g. there is no way to chainload something unless
using BIOS.

Could you give more details what exactly are you trying to do?