Reduce steps for LVM group creation

Author: electrocucaracha

node.sh

@@ -91,11 +91,8 @@ if [ -n "${cinder_volumes-}" ]; then
     if ! command -v vgs; then
         curl -fsSL http://bit.ly/install_pkg | PKG="lvm2" bash
     fi
-    # Ensure that the volume is empty
-    sudo dd if=/dev/zero of="$cinder_volumes" bs=512 count=1
-
     # Creation of cinder LVM
-    sudo vgcreate cinder-volumes "$cinder_volumes"
+    sudo vgcreate cinder-volumes "$cinder_volumes" -f
     sudo vgs
     sudo pvdisplay