diff --git a/Jenkinsfile b/Jenkinsfile
index 7a46844b..1252f6d5 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -52,8 +52,23 @@ pipeline {
             steps {
                 echo 'Cleanup...'
                 sh """
-                docker rmi `docker images | grep '<none>' | grep -v IMAGE | awk '{ print \$3 }' | xargs` | true
-                docker rm `docker ps -a | grep Exited | awk '{ print \$1 }' | xargs` | true
+                # remove unused containers
+                container_ids=`docker ps -a | grep Exited | awk '{ print \$1 }' | xargs`
+                if [ \$container_ids -eq "" ];
+                then
+                    :
+                else
+                    docker rm \$container_ids
+                fi
+
+                # remove unused images
+                image_ids=`docker images | grep '<none>' | grep -v IMAGE | awk '{ print \$3 }' | xargs`
+                if [ \$image_ids -eq "" ];
+                then
+                    :
+                else
+                    docker rmi \$image_ids
+                fi
                 """
             }
         }