diff --git a/tools/update_containers.sh b/tools/update_containers.sh
index 139bd942a52b152a2ce7f3edd63d5b6b07ba2cff..c51f6b8a97f1c183cf06c14bdde3d3bde5f3d377 100755
--- a/tools/update_containers.sh
+++ b/tools/update_containers.sh
@@ -8,7 +8,7 @@ echo "Pulling images"
 echo ""
 
 # pull updated images 
-docker-compose $docker_compose_files pull
+docker-compose $DOCKER_COMPOSE_FILES pull
 
 echo "Building images"
 echo ""