[linux-lvm] Fun little horror story -- please add to FAQ if it isn't already documented

[Ben Holness]

> Upon the next reboot, the initrd ran fine... found and activated the
> lv's... but the kernel said "no root partition" and hung.  I could
> rescue boot the system from the SuSE CD -- everything was there... I
> finally added a "vgdisplay -v" to the initrd's linuxrc, and
> that showed me the problem.
>
> The file system it was trying to mount was, to lilo, the device "3a:03"
> (major device number 58, minor 3), but, once I'd removed the old lv for
> extra disk space, any new vgscan during initrd assigned my new root lv
> to minor device number 2.  "root=/dev/..." doesn't help, for lvm (it
> doesn't like the name).  There was no longer an lvm minor device 3 to
> mount.

This looks like the same problem that I am having, although I haven't
removed any logical volumes!

I am not 100% sure how to find the device number, but common sense tells me
that it is the "Block #" at the bottom of the logical volume information, in
which case my root LV is Block # 58:1

> Once I saw the problem, I recue booted and chrooted to my new lvm, and
> manually changed the minor number before running lilo.

Please can you tell me how you changed this?

Cheers,

Ben