# Source: https://docs.datadoghq.com/security/default_rules/mtg-wt7-w4j.md

---
title: >-
  The kubelet server certificate rotation on controller-manager should be
  enabled
description: Datadog, the leading service for cloud-scale monitoring.
breadcrumbs: >-
  Docs > Datadog Security > OOTB Rules > The kubelet server certificate rotation
  on controller-manager should be enabled
---

# The kubelet server certificate rotation on controller-manager should be enabled
Classification:complianceFramework:cis-kubernetesControl:1.3.6 
## Description{% #description %}

Enable kubelet server certificate rotation on controller-manager.

## Rationale{% #rationale %}

`RotateKubeletServerCertificate` causes the kubelet to both request a serving certificate after bootstrapping its client credentials and rotate the certificate as its existing credentials expire. This automated periodic rotation ensures that the there are no downtimes due to expired certificates and thus addressing availability in the CIA security triad.

*Note*: This recommendation only applies if you let kubelets get their certificates from the API server. In case your kubelet certificates come from an outside authority/tool (e.g. Vault) then you need to take care of rotation yourself.

## Audit{% #audit %}

Run the following command on the master node:

```
ps -ef | grep kube-controller-manager
```

Verify that `RotateKubeletServerCertificate` argument exists and is set to `true`.

## Remediation{% #remediation %}

Edit the Controller Manager pod specification file `/etc/kubernetes/manifests/kube-controller-manager.yaml` on the master node and set the `--feature-gates` parameter to include `RotateKubeletServerCertificate=true`.

```
--feature-gates=RotateKubeletServerCe`rtificate=true
```

## Impact{% #impact %}

None

## Default value{% #default-value %}

By default, `RotateKubeletServerCertificate` is not set.

## References{% #references %}

1. [https://kubernetes.io/docs/admin/kubelet-tls-bootstrapping/#approval-controller](https://kubernetes.io/docs/admin/kubelet-tls-bootstrapping/#approval-controller)
1. [https://github.com/kubernetes/features/issues/267](https://github.com/kubernetes/features/issues/267)
1. [https://github.com/kubernetes/kubernetes/pull/45059](https://github.com/kubernetes/kubernetes/pull/45059)
1. [https://kubernetes.io/docs/admin/kube-controller-manager/](https://kubernetes.io/docs/admin/kube-controller-manager/)

## CIS controls{% #cis-controls %}

Version 6 14.2 Encrypt All Sensitive Information Over Less-trusted Networks All communication of sensitive information over less-trusted networks should be encrypted. Whenever information flows over a network with a lower trust level, the information should be encrypted.

Version 7 14.4 Encrypt All Sensitive Information in Transit Encrypt all sensitive information in transit.