[CentOS] "Can't find root device" with lvm root after moving drive on CentOS 6.3

Mon Mar 25 05:29:51 UTC 2013
Gordon Messmer <yinyang at eburg.com>

On 03/22/2013 08:27 PM, Joakim Ziegler wrote:
> So, after all this, my question is, how do I make Dracut (I'm assuming)
> understand that this LVM volume is my root device and pick it up
> automatically?

I've looked through Dracut trying to spot circumstances that might cause 
the problem that you've described, but came up with nothing.  udev 
should be scanning block devices as they become available, and setting 
up any logical volumes on all of the available block devices.

It may be useful to capture some information in the debugging shell, 
before running vgscan.

As suggested in the fedora debugging document, capture the output of the 
following commands to get a better idea of what the kernel knows about 
block devices before you manually start the volumes, and maybe that'll 
lead us to some conclusion about why the devices aren't found.

lvm pvdisplay
lvm vgdisplay
lvm lvdisplay