diff --git a/README.md b/README.md
index d21e4ce..c8a82a8 100644
--- a/README.md
+++ b/README.md
@@ -15,6 +15,10 @@ AdGuard Home Server
 
          $ sudo yunohost app install https://github.com/YunoHost-Apps/adguard_ynh
 
+         Fail to start ?
+
+         $ netstat -tlnp | grep 53
+
  
 ### Upgrade this package: