diff --git a/devstack/plugin.sh b/devstack/plugin.sh
index 88743007b..ce9e4915a 100644
--- a/devstack/plugin.sh
+++ b/devstack/plugin.sh
@@ -78,7 +78,7 @@ function build_octavia_worker_image {
     export PARAM_OCTAVIA_AMP_IMAGE_SIZE='-s '$OCTAVIA_AMP_IMAGE_SIZE
     fi
     if ! [ -f $OCTAVIA_AMP_IMAGE_FILE ]; then
-        $OCTAVIA_DIR/diskimage-create/diskimage-create.sh $octavia_dib_tracing_arg -o $OCTAVIA_AMP_IMAGE_FILE ${PARAM_OCTAVIA_AMP_BASE_OS:-''} ${PARAM_OCTAVIA_AMP_DISTRIBUTION_RELEASE_ID:-''} ${PARAM_OCTAVIA_AMP_IMAGE_SIZE:-''}
+        $OCTAVIA_DIR/diskimage-create/diskimage-create.sh $octavia_dib_tracing_arg -o $OCTAVIA_AMP_IMAGE_FILE ${PARAM_OCTAVIA_AMP_BASE_OS:-} ${PARAM_OCTAVIA_AMP_DISTRIBUTION_RELEASE_ID:-} ${PARAM_OCTAVIA_AMP_IMAGE_SIZE:-}
     fi
     upload_image file://${OCTAVIA_AMP_IMAGE_FILE} $TOKEN