LVM and grub

[Gene Heskett]

On Monday 11 February 2008, Timothy Murphy wrote:
>Mikkel L. Ellertson wrote:
>>> I set up an LVM partitioning scheme on one computer,
>>> with /boot on /dev/sda3 outside LVM .
>>> But grub could not access / because LVM was not activated.
>>> This made me wonder:
>>>
>>> 1. Is there any way of asking grub to activate LVM
>>> (eg run "vchange -a y") before it looks for the / partition?
>>>
>>> 2. Is there any argument one could add to the kernel line
>>> to the same effect?
>>>
>>> In the end I deleted the LVM, and used ordinary partitions,
>>> so the question is purely academic.
>>
>> With /boot on its own partition, Grub does not need to access the
>> root partition. This is good because Grub does not understand LVM.
>> The thing you have to remember when using a separate /boot partition
>> is that the paths that Grub uses do not start with /boot. You would
>> use something like:
>>
>> title Fedora (2.6.23.14-115.fc8)
>>          root (hd0,2)
>>          kernel /vmlinuz-2.6.23.14-115.fc8 ro
>> root=/dev/VolGroup00/LogVol00 rhgb quiet
>>          initrd /initrd-2.6.23.14-115.fc8.img
>>
>> As far as Grub is concerned, your /boot directory is its root
>> directory. This is what the root (hd0,2) is telling Grub.
>
>My problem was that root=/dev/VolGroup00/... was not found,
>since LVM was not active at at that point.
>The boot started, but failed with "/dev/root not found".
>
Huh?  I've been booting with exactly that command line argument for quite some 
time now.  Year (how old is FC6?) or more.  Perhaps your hd(0,2) is too far 
into the disk and the bios is having problems?  One of the many reasons 
the /boot partition is the first one here, and something in the back of my 
mind says it cannot be a directory within an LVM, but must be a separate 
partition.

-- 
Cheers, Gene
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