WTF Grub syntax "root=LABEL=/"

[Paul Dickson]

On Sat, 22 Nov 2003 08:24:37 -0700, Ed Skinner wrote:

> I must be looking in all the wrong places for the answer...
> In my /boot/grub/grub.conf file, the kernel line is:
> 
> kernel /vmlinuz-2.4.22-skinner ro root=LABEL=/
> 
> But darned if I can find where the "root=LABEL=/" meaning is spelled out. "man 
> grub" sends me to "info grub" but it never mentions this particular form of 
> the command. It gives examples such as "root=/dev/hda1" but never a form with 
> two equals signs.

It's an option passed by grub to the kernel.

> I presume this syntax means to look for the partition that is labelled as "/" 
> but, again, I must be looking in the wrong places -- how do I display and 
> then modify partition labels, if that's what's going on.
> 
> I'm playing with a 2.6.0-test9 kernel and the only way I can get it to try and 
> boot is to modify the corresponding line for that kernel from "root=LABEL=/" 
> to "root=/dev/hda1" (which is my "/" partition). I'm having other (possibly 
> unrelated) problems after that but, since this "problem" is so early in the 
> boot, I'm hoping it may account for some of the subsequent problems.
> 
> Interestingly, the grub.conf for my normal kernel (2.4.22-skinner) is the one 
> shown above and it works just fine with "root=LABEL=/".

If you want this feature in 2.6, you'll need to include support (parsing
via userspace tools) in a initrd.  The kernel processing of this option
has been removed.  As part of this toolset, you might look at devlabel.

	-Paul