diff --git a/docs/02-certificate-authority.md b/docs/02-certificate-authority.md
index c33e51a..d76ecee 100644
--- a/docs/02-certificate-authority.md
+++ b/docs/02-certificate-authority.md
@@ -187,6 +187,7 @@ cfssl gencert \
   -ca-key=ca-key.pem \
   -config=ca-config.json \
   -profile=kubernetes \
+  -hostname=hosts \
   kubernetes-csr.json | cfssljson -bare kubernetes
 ```