diff --git a/lib/neutron_plugins/ovn_agent b/lib/neutron_plugins/ovn_agent
index e646258..699bd54 100644
--- a/lib/neutron_plugins/ovn_agent
+++ b/lib/neutron_plugins/ovn_agent
@@ -558,7 +558,7 @@
         sample_file=$NEUTRON_DIR/etc/neutron_ovn_metadata_agent.ini.sample
         config_file=$OVN_META_CONF
     fi
-    if [ -n ${config_file} ]; then
+    if [ -n "$config_file" ]; then
         sudo install -d -o $STACK_USER $NEUTRON_CONF_DIR
 
         mkdir -p $NEUTRON_DIR/etc/neutron/plugins/ml2