diff --git a/config-sample.yaml b/config-sample.yaml
index 1e18cd116..5884b9d1d 100644
--- a/config-sample.yaml
+++ b/config-sample.yaml
@@ -9,6 +9,7 @@ log_level: info
 # clients could connect to any node and be routed to the same room
 redis:
   address: redis.host:6379
+#  db: 0
 #  username: myuser
 #  password: mypassword