diff --git a/main.sh b/main.sh
index 454f68c..05b6c0f 100755
--- a/main.sh
+++ b/main.sh
@@ -41,7 +41,7 @@ target_phy_disk() {
 target_phy_id() {
 	local i
 	local f2
-	if ! echo "${TARGET_PHY_DISK}" | grep -q vd ; then
+	if echo "${TARGET_PHY_DISK}" | grep -qv vd ; then
 		for i in $(find /dev/disk/by-id ! -type d | grep -v part); do
 			if realpath "${i}" | grep -q -i "${TARGET_PHY_DISK}"; then
 				if echo "${i}" | grep -v "wwn" | grep -q -v "eui"; then