If you get issues regarding failed disks on some linux machines and you may be forced to recreate the VG structure here are the necessary steps to do it:

ONLY IF /etc/lvm/backup/_VG_NAME_ exists
1. recover the UID of the failed disk
sed -n '/pv0 /{n;p;}' /etc/lvm/backup/vg_root |sed 's/.*"\(.*\)\"/\1/'
1.1 assign the value to $OLD_UID variable
2. prepare the new disk with the old UID
pvcreate -ff -v -u $OLD_UID /dev/sdb1
3. restore VG structure
vgcfgrestore -f /etc/lvm/backup/vg_root vg_root
3.1 reactivate VG
vgchange -ay vg_root
4. recreate the FS & mount them