Backend defined in client test
diff --git a/tests/pillar/client.sls b/tests/pillar/client.sls
index 42b2deb..b970e72 100644
--- a/tests/pillar/client.sls
+++ b/tests/pillar/client.sls
@@ -5,6 +5,7 @@
     read_interval: 60
     backend:
       carbon:
+        engine: carbon
         host: 127.0.0.1
         port: 2023