[linux-lvm] Unusually long boot times with LVM Snapshots

[Bryn M. Reeves]

On Tue, Nov 24, 2020 at 05:27:21PM +0530, Sreyan Chakravarty wrote:
> But I am unable to boot now due to these errors:
> 
> Nov 24 10:44:00 localhost.HPNotebook dracut-initqueue[861]: Scanning
> devices dm-0  for LVM logical volumes vgfedora/fedora
> Nov 24 10:44:00 localhost.HPNotebook dracut-initqueue[886]: inactive
> '/dev/vgfedora/pool00' [929.75 GiB] inherit
> Nov 24 10:44:00 localhost.HPNotebook dracut-initqueue[886]: inactive
> '/dev/vgfedora/fedora' [700.00 GiB] inherit
> Nov 24 10:44:00 localhost.HPNotebook dracut-initqueue[888]: modprobe:
> FATAL: Module dm-thin-pool not found in directory
> /lib/modules/5.8.18-200.fc32.x86_64
> Nov 24 10:44:00 localhost.HPNotebook dracut-initqueue[888]:
> /usr/sbin/modprobe failed: 1
> Nov 24 10:44:00 localhost.HPNotebook dracut-initqueue[888]: Can't process
> LV vgfedora/fedora: thin target support missing from kernel?
> 
> I have tried to mark the volumes as active by :
> 
>                 lvchange -kn vgfedora/pool00
>                 lvchange -kn vgfedora/fedora
> 
> But no change.
> 
> 
> 
> How do I add the dm-thin-pool module ? I can't even boot.

Most likely you are just missing the dm-thin-pool module in the dracut
initramfs image.

You can re-build it with the following command:

  # dracut -f /boot/initramfs-$(uname -r).img $(uname -r)

If the running kernel matches the initramfs you want to rebuild then
you can leave out the file and kernel version:

  # dracut -f

To build an initramfs with only the drivers that the running host
uses add the -H switch (the dm-thin-pool module must be loaded at
the time you run dracut for this to work):

  # dracut -fH

See the dracut man page for more details.

Regards,
Bryn.