diff --git a/cluster/ansible/README.md b/cluster/ansible/README.md
index 96252e0b..529410a5 100644
--- a/cluster/ansible/README.md
+++ b/cluster/ansible/README.md
@@ -48,4 +48,12 @@ Using `sysctl -p` to make kernel params effect.
 
 ## How to use ?
 
-TODO
\ No newline at end of file
+### Cluster Scaling
+
+If you want to scale nodes in cluster, you can execute script `upgrade-cluster.sh` after environment initialized.
+
+#### Tips - ANONYMOUS AUTH ENABLING BEFORE SCALE
+
+`kubeadm` using bootstrap token to join newly added nodes into cluster, which means we need **enable anonymous authentication** for `kube-apiserver` temporally.
+
+You need edit `/etc/kubernetes/manifests/kube-apiserver.yaml` on master-01 node and set `--anonymous-auth=true` and you must recovery it to `false` when cluster has been scaled.