Re: Root missed at boot up.
On Fri, Oct 14, 2011 at 02:23:25AM BST, Magicloud Magiclouds wrote:
> The error was "cannot find root $UUID" specified in root bootflag.
> I thought something wrong so the uuid of the root was changed. So in
> busybox, I `ls -l /dev/disk/by-uuid`, I got two items: dm-1(I am not
> quite sure now, maybe it displayed dm-0.), sda1. I knew sda1 was /boot
> partition, so I changed boot cmdline with the uuid I found temporally.
> Still cannot boot up. No root found with the new uuid.
> Then I changed bootflag root to device name
> (/dev/mapper/vgroot-lvroot). Then things worked.
> In the boot-uped system, I `ls -l /dev/disk/by-uuid`, and found
> that, the uuid of root is still the same as in boot cmdline, and the
> device is dm-0. dm-1 is the swap.
Could you do it again or on a running system and redirect the output to
a file, then attach the file to an email?
> So to sum up, my system cannot find lvm root device (dm-0) and its
> uuid at boot up. But can be booted up by its device name
> (/dev/mapper/vgroot-lvroot). And in boot-uped system, the root device
> looks fine in /dev.
> What happened? How to fix this?
You hadn't mentioned what architecture you're running and what
bootloader you're using.
What if you regenerate initrd/initramfs?