[Wylug-help] USB Flash: device numbers, filenames and grub

[John Hodrien]

On Sat, 27 Jan 2007, Dave Fisher wrote:

> It certainly enables one to mount an device in a consistent place,
> regardless of the kernel's default name, by creating a symlink
> 'on-the-fly'.

Indeed.  I use that for creating predictable USB keyboard and mouse names on a
system with many of each.

> From what my experiments indicate, the personal udev rules are not yet
> applied at the time when the kernel needs to mount the root filesystem
> (or at least, when the kernel needs to know the filesystem device
> address).

If you're using an initrd then don't assume; tear it apart and look.  It's
either going to be a cpio archive or a ext2 filesystem, so poke around and see
what it does.

> One possibility that occurred to me was that the suggested personal
> rules file (/etc/udev/rules.d/10-local.rules) might not be loaded
> sufficiently early for its rules to apply.
>
> Even if this were true, I'm not sure whether it is feasible to load it
> earlier, and in a safe/reliable way.
>
> Does anyone know something about that?

I'd be tempted to try and ignore it all together.  If you use something that
doesn't rely on consistent device naming then perhaps you'll have more
success:  LVM.  Basically this scans available devices, rather than assuming
their location.

jh

-- 
"He who joyfully marches in rank and file has already earned my contempt. He
  has been given a large brain by mistake, since for him the spinal cord would
  suffice."                                           -- Albert Einstein