pvremove could not find the device in my case. It said "Couldn't find device. Check your filters?" with -ff and "Physical Volume /dev/sda5 note found" without -ff. pvck and pvscan were of no use identifying the label, however I knew that I had moved LVM from /dev/sda5 to /dev/sda6 using the alternate installer (similar to comments above).
pvremove could not find the device in my case. It said "Couldn't find device. Check your filters?" with -ff and "Physical Volume /dev/sda5 note found" without -ff. pvck and pvscan were of no use identifying the label, however I knew that I had moved LVM from /dev/sda5 to /dev/sda6 using the alternate installer (similar to comments above).
I found this post below and was able to see the label myself. www.redhat. com/archives/ linux-lvm/ 2008-February/ msg00011. html
http://
dd if=/dev/sda5 bs=1k count=1 | hexdump -e '"%_p"'
so there it is. but when I use pvremove -vvvv /dev/sda5 I can see the "Skipping md component device" rule being applied. How do I turn this off??
Interestingly, I have another device that is a raid device, that has LVM on it, and it looks the same, so I get how grub2 is getting confused.
The solution was to turn md detection off in /etc/lvm/lvm.conf and re-run the pvremove command. The labels were "successfully wiped".