diff --git a/README.md b/README.md
index e3e9991..2262427 100644
--- a/README.md
+++ b/README.md
@@ -5,8 +5,9 @@ The metadata frontend proxy is a web related gateway to reach backend services f
 
 The proxy service is complex and has many parameters to configure by users.
 
-There is two important parts
+There is three important parts
 
+- core-dns service which is needed for stable proxy availability
 - public proxy service (1 haproxy loadbalancer and 2 haproxy backend proxies)
 - smarthost proxy service (1 haproxy loadbalancer and 2 nginx backend proxies with builtin SSL certificates termination processes)