[CentOS] KVM won't boot after update to 1804

Wed May 23 14:43:50 UTC 2018
Ranbir <m3freak at thesandhufamily.ca>

On Wed, 2018-05-23 at 10:29 -0400, Ranbir wrote:
> Warning: /dev/centos_webman03/root does not exist
> Warning: /dev/centos_webman03/swap does not exist
> Warning: /dev/mapper/centos_webman11-root does not exist
> dracut:/# lvm vgchange -a y
>   6 logical volume(s) in volume group "centos_webman11" now active
> dracut:/# ln -s /dev/mapper/centos_webman11-root /dev/root
> dracut:/# exit
> logout
> How do I fix this problem? Does anyone have any idea about what
> caused
> this in the first place?

Ah, crap. I just figured out what the problem is. I had changed the
name of the VG and didn't update the grub2 config to reflect that
change. So, of course, no amount of grub2 updating was going to fix the
problem because the devices that had "webman03" truly didn't exist
(they now had "webman11" in them).

After fixing that mistake, the server booted up just fine.

Sorry for the noise!