I have a server (Ubuntu 18.04) with a number of LVM Logical Volumes. After a routine reboot one of them does not come back. After some investigation this is where I am at:
the physical disk is an iSCSI device and it is seen by the kernel as /dev/sdc (no errors and the correct size)
lvmdiskscan -v sees the PV on /dev/sdc
> lvmdiskscan -v ... /dev/sdc [ 72.76 TiB] LVM physical volume
- blkid returns the UUID that I can also find in the LVM configuration
... /dev/sdc: UUID="fvUXXf-pVOF-EPnn-c8eg-tZ5S-iMVW-wsSFDy" TYPE="LVM2_member"
this entry lacks a PARTUUID entry that other LVs on the system have. Is this a clue? I could not quite connect this piece of info with anything that helps me further.
pvscan does not report /dev/sdc
pvdisplay does not seem to know about this PV
> pvdisplay /dev/sdc Failed to find physical volume "/dev/sdc"
Anybody who can point me in the right direction?
Edited to add the output of pvck -t
pvck -t /dev/sdc TEST MODE: Metadata will NOT be updated and volumes will not be (de)activated. Found label on /dev/sdc, sector 1, type=LVM2 001 Found text metadata area: offset=4096, size=1044480
Also useful to know that this LV was originally made on Ubuntu 14.04, and has been running perfectly fine on Ubuntu 18.04.
Additional output from lvmdiskscan below. This output does not look different from what I get for other VGs on the system. LVs first appear to be orphan, then the they are associated with a VG, and they become usable. But for r3vg this does not happen.
lvm: Reading label from device /dev/sdc lvm: Opened /dev/sdc RO O_DIRECT lvm: /dev/sdc: block size is 4096 bytes lvm: /dev/sdc: physical block size is 512 bytes lvm: /dev/sdc: lvm2 label detected at sector 1 lvm: lvmcache /dev/sdc: now in VG #orphans_lvm2 (#orphans_lvm2) with 0 mda(s). lvm: /dev/sdc: PV header extension version 2 found lvm: /dev/sdc: Found metadata at 5632 size 1015 (in area at 4096 size 1044480) for r3vg (Rpn2x9KOivnVd3m6gM9Rf2p3SYkRFm00) lvm: lvmcache has no info for vgname "r3vg" with VGID Rpn2x9KOivnVd3m6gM9Rf2p3SYkRFm00. lvm: lvmcache has no info for vgname "r3vg". lvm: lvmcache /dev/sdc: now in VG r3vg with 1 mda(s). lvm: lvmcache /dev/sdc: VG r3vg: set VGID to Rpn2x9KOivnVd3m6gM9Rf2p3SYkRFm00. lvm: lvmcache /dev/sdc: VG r3vg: set creation host to leitrim. lvm: lvmcache /dev/sdc: VG r3vg: stored metadata checksum 0x54affad5 with size 1015. lvm: Closed /dev/sdc lvm: /dev/sdc: using cached size 156250918912 sectors lvm: /dev/sdc [ 72.76 TiB] LVM physical volume lvm: 7 disks lvm: 3 partitions lvm: 1 LVM physical volume whole disk lvm: 2 LVM physical volumes lvm: Setting global/notify_dbus to 1 lvm: Completed: lvmdiskscan -dddddd