I have tried to reproduce the grub error in a PVE 8 VM, but have not succeeded so far.
I tried the following: Repeatedly create/remove LVM logical volumes to trigger metadata updates, and reboot once the current metadata starts close to the end of the metadata ring buffer, wraps around and continues at the beginning of the metadata ring buffer.
vgscan -vvv indicates this situation with a log message like this (note the
size A (+B) with nonzero B, indicating that B bytes reside at the beginning of the metadata ring buffer):
Code:
Reading metadata summary from /dev/... at 1036800 size 11776 (+43548)
If this is the case, reboot. Under PVE 7.4 / Debian Bullseye, grub 2.06-3 then threw the
disk 'lvmid/...' not found error and failed to boot. This was due to a bug in the LVM metadata parser in the wraparound case of the metadata ring buffer. However, under PVE 8 / Debian Bookworm, grub 2.06-13 boots just fine.
So the
disk 'lvmid/...' not found error on boot with PVE 8 / Debian Bookworm and grub 2.06
-13 is probably caused by a different bug. However, since the workaround is the same (trigger an LVM metadata update so it resides in one contiguous section in the metadata ring buffer), the new bug may be related to the wraparound case of the metadata ring buffer as well. However, currently I don't see anything wrong with the LVM metadata parser in grub 2.06
-13. So it would be great if we could get some more debugging information.
For anyone who encounters this bug with PVE
8 / grub 2.06
-13, could you gather and post the following data
before triggering the metadata update workaround? On the live ISO, do the following:
- Find out the path of the LVM physical volume containing the root partition by running
pvs and finding the correct physical volume
- Post the output of
pvdisplay and vgdisplay
- Post the output of
pvck PV --dump headers (replace PV with the physical volume path from above). For example, if the physical volume is /dev/sda3, please provide the output of pvck /dev/sda3 --dump headers
- Post the output of
grub-fstest --version and grub-fstest -v PV ls (replace PV with the physical volume path from above)
- Dump and gzip the metadata section to a file:
head -c 1048576 PV | gzip > /tmp/metadata.gz (replace PV with the physical volume path from above). Please attach the file /tmp/metadata.gz. Note that if you use the LVM volume group (or a thin pool) as VM storage, the metadata will contain e.g. snapshot names, so please only attach them if you're okay with that.
