But pvcreate is expecting a PV path as the last argument (the device to be initialised as a PV), not a VG name (are you confusing this with the vgcfgrestore arguments?).

This works just fine for me:

# pvcreate -f –uuid 6cxF7v-f0XU-3EK1-QhA2-YSVT-yEe3-vQnE09 –restorefile /etc/lvm/archive/l0_00000.vg /dev/loop0 Can't initialize physical volume “/dev/loop0“ of volume group „l0“ without -ff

# pvcreate -ff –uuid 6cxF7v-f0XU-3EK1-QhA2-YSVT-yEe3-vQnE09 –restorefile /etc/lvm/archive/l0_00000.vg /dev/loop0

Really INITIALIZE physical volume “/dev/loop0“ of volume group „l0“ [y/n]? y

WARNING: Forcing physical volume creation on /dev/loop0 of volume group „l0“

Physical volume "/dev/loop0" successfully created

# vgcfgrestore -f /etc/lvm/archive/l0_00000.vg l0

Restored volume group l0