diff --git a/lib/neutron-legacy b/lib/neutron-legacy
old mode 100644
new mode 100755
index c244bc54cd..c74c844a0c
--- a/lib/neutron-legacy
+++ b/lib/neutron-legacy
@@ -326,7 +326,9 @@ ENABLE_METADATA_NETWORK=${ENABLE_METADATA_NETWORK:-False}
 # ---------------------------------
 
 # Please refer to ``lib/neutron_plugins/README.md`` for details.
-source $TOP_DIR/lib/neutron_plugins/$Q_PLUGIN
+if [ -f $TOP_DIR/lib/neutron_plugins/$Q_PLUGIN ]; then
+    source $TOP_DIR/lib/neutron_plugins/$Q_PLUGIN
+fi
 
 # Agent loadbalancer service plugin functions
 # -------------------------------------------