backupninja metadata fix

Change-Id: I35093e7768037c25bb77d5316515e8f18d2c7d85
diff --git a/metadata/service/client/single.yml b/metadata/service/client/single.yml
index d228a76..6b1278d 100644
--- a/metadata/service/client/single.yml
+++ b/metadata/service/client/single.yml
@@ -4,11 +4,12 @@
 - backupninja
 parameters:
   _param:
-    backupninja_backup_host: backupninja-server-host
+    backupninja_backup_host: ${_param:infra_config_address}
+    backupninja_engine: rsync
   backupninja:
     client:
       enabled: true
       target:
-        engine: rsync
+        engine: ${_param:backupninja_engine}
         host: ${_param:backupninja_backup_host}
         user: backupninja