diff --git a/docs/admin/authentication.md b/docs/admin/authentication.md
index df5f1e0a72d..8ab706f2a5f 100644
--- a/docs/admin/authentication.md
+++ b/docs/admin/authentication.md
@@ -118,18 +118,22 @@ Finally, add these parameters
 into apiserver start parameters.
 
 **easyrsa** can be used to manually generate certificates for your cluster.
+
 1.  Download, unpack, and initialize the patched version of easyrsa3.
-    `curl -L -O https://storage.googleapis.com/kubernetes-release/easy-rsa/easy-rsa.tar.gz`
-    `tar xzf easy-rsa.tar.gz`
-    `cd easy-rsa-master/easyrsa3`
-    `./easyrsa init-pki`
-1.  Generate a CA. (--batch set automatic mode. --req-cn default CN to use.)
-    `./easyrsa --batch "--req-cn=${MASTER_IP}@date +%s" build-ca nopass`
+
+          curl -L -O https://storage.googleapis.com/kubernetes-release/easy-rsa/easy-rsa.tar.gz
+          tar xzf easy-rsa.tar.gz
+          cd easy-rsa-master/easyrsa3
+          ./easyrsa init-pki
+1.  Generate a CA. (`--batch` set automatic mode. `--req-cn` default CN to use.)
+
+          ./easyrsa --batch "--req-cn=${MASTER_IP}@`date +%s`" build-ca nopass
 1.  Generate server certificate and key.
     (build-server-full [filename]: Generate a keypair and sign locally for a client or server)
-    `./easyrsa --subject-alt-name="${MASTER_IP}" build-server-full kubernetes-master nopass`
-1.  Copy /pki/ca.crt  /pki/issued/kubernetes-master.crt
-    /pki/private/kubernetes-master.key to your directory.
+
+          ./easyrsa --subject-alt-name="IP:${MASTER_IP}" build-server-full kubernetes-master nopass
+1.  Copy `pki/ca.crt`  `pki/issued/kubernetes-master.crt`
+    `pki/private/kubernetes-master.key` to your directory.
 1.  Remember fill the parameters
     `--client-ca-file=/yourdirectory/ca.crt`
     `--tls-cert-file=/yourdirectory/server.cert`
@@ -137,6 +141,7 @@ into apiserver start parameters.
     and add these into apiserver start parameters.
 
 **openssl** can also be use to manually generate certificates for your cluster.
+
 1.  Generate a ca.key with 2048bit
     `openssl genrsa -out ca.key 2048`
 1.  According to the ca.key generate a ca.crt.  (-days set the certificate effective time).