Helm

Installing with Helm

cert-manager provides Helm charts as a first-class method of installation on both Kubernetes and OpenShift.

Be sure never to embed cert-manager as a sub-chart of other Helm charts; cert-manager manages non-namespaced resources in your cluster and care must be taken to ensure that it is installed exactly once.

Prerequisites

Install Helm version 3 or later.
Install a supported version of Kubernetes or OpenShift.
Read Compatibility with Kubernetes Platform Providers if you are using Kubernetes on a cloud platform.

Installing cert-manager

1. Add the Helm repository

This repository is the only supported source of cert-manager charts. There are some other mirrors and copies across the internet, but those are entirely unofficial and could present a security risk.

Notably, the "Helm stable repository" version of cert-manager is deprecated and should not be used.

helm repo add jetstack https://charts.jetstack.io --force-update

2. Install cert-manager

To install the cert-manager Helm chart, use the Helm install command as described below.

helm install \
  cert-manager jetstack/cert-manager \
  --namespace cert-manager \
  --create-namespace \
  --version v1.16.2 \
  --set crds.enabled=true

3. (optional) Verify installation

Once you have deployed cert-manager, you can verify the installation.

Installation options

A full list of available Helm values is on cert-manager's ArtifactHub page.

The example below shows how to tune the cert-manager installation by overwriting the default Helm values:

helm install \
  cert-manager jetstack/cert-manager \
  --namespace cert-manager \
  --create-namespace \
  --version v1.16.2 \
  --set crds.enabled=true \
  --set prometheus.enabled=false \  # Example: disabling prometheus using a Helm parameter
  --set webhook.timeoutSeconds=4   # Example: changing the webhook timeout using a Helm parameter

Installing cert-manager as subchart

If you have configured cert-manager as a subchart all the components of cert-manager will be installed into the namespace of the helm release you are installing.

There may be a situation where you want to specify the namespace to install cert-manager different to the umbrella chart's namespace.

This is a known issue with helm and subcharts, that you can't specify the namespace for the subchart and is being solved by most public charts by allowing users to set the namespace via the values file, but needs to be a capability added to the chart by the maintainers.

This capability is now available in the cert-manager chart and can be set either in the values file or via the --set switch.

Example usage

Below is an example Chart.yaml with cert-manager as a subchart

apiVersion: v2
name: example_chart
description: A Helm chart with cert-manager as subchart
type: application
version: 0.1.0
appVersion: "0.1.0"
dependencies:
  - name: cert-manager
    version: v1.16.2
    repository: https://charts.jetstack.io
    alias: cert-manager
    condition: cert-manager.enabled

You can then override the namespace in 2 ways:

In Values.yaml file

cert-manager: #defined by either the name or alias of your dependency in Chart.yaml
  namespace: security

In the helm command using --set

helm install example example_chart \
  --namespace example \
  --create-namespace \
  --set cert-manager.namespace=security

The above example will install cert-manager into the security namespace.

Output YAML

Instead of directly installing cert-manager using Helm, a static YAML manifest can be created using the Helm template command. This static manifest can be tuned by providing the flags to overwrite the default Helm values:

helm template \
  cert-manager jetstack/cert-manager \
  --namespace cert-manager \
  --version v1.16.2 \
  --set crds.enabled=true \
  # --set prometheus.enabled=false \   # Example: disabling prometheus using a Helm parameter
  > cert-manager.custom.yaml

ℹ️ The helm template command will not output a Namespace resource and ignores the --create-namespace flag. You must ensure the namespace you are deploying the generated YAML to exists.

Uninstalling

Warning: To uninstall cert-manager you should always use the same process for installing but in reverse. Deviating from the following process whether cert-manager has been installed from static manifests or Helm can cause issues and potentially broken states. Please ensure you follow the below steps when uninstalling to prevent this happening.

Before continuing, ensure that all cert-manager resources that have been created by users have been deleted. You can check for any existing resources with the following command:

kubectl get Issuers,ClusterIssuers,Certificates,CertificateRequests,Orders,Challenges --all-namespaces

Once all these resources have been deleted you are ready to uninstall cert-manager using the procedure determined by how you installed.

Uninstalling with Helm

Uninstalling cert-manager from a helm installation is a case of running the installation process, in reverse, using the delete command on both kubectl and helm.

$ helm uninstall cert-manager -n cert-manager

These resources were kept due to the resource policy:
[CustomResourceDefinition] certificaterequests.cert-manager.io
[CustomResourceDefinition] certificates.cert-manager.io
[CustomResourceDefinition] challenges.acme.cert-manager.io
[CustomResourceDefinition] clusterissuers.cert-manager.io
[CustomResourceDefinition] issuers.cert-manager.io
[CustomResourceDefinition] orders.acme.cert-manager.io

release "cert-manager" uninstalled

As shown in the output, the CustomResourceDefinition for Issuers,ClusterIssuers,Certificates,CertificateRequests,Orders and Challenges are not removed by the Helm uninstall command. This is to prevent data loss, as removing the CustomResourceDefinition would also remove all instances of those resources.

☢️ This will remove all Issuers,ClusterIssuers,Certificates,CertificateRequests,Orders and Challenges resources from the cluster:
kubectl delete crd \
  issuers.cert-manager.io \
  clusterissuers.cert-manager.io \
  certificates.cert-manager.io \
  certificaterequests.cert-manager.io \
  orders.acme.cert-manager.io \
  challenges.acme.cert-manager.io

⚠️ cert-manager versions prior to v1.15.0 do not keep the CustomResourceDefinition on uninstall and will remove all Issuers,ClusterIssuers,Certificates,CertificateRequests,Orders and Challenges resources from the cluster. Make sure to back up your cert-manager resources before uninstalling cert-manager if you are using a version prior to v1.15.0. Or upgrade to v1.15.0 before uninstalling.

Namespace Stuck in Terminating State

If the namespace has been marked for deletion without deleting the cert-manager installation first, the namespace may become stuck in a terminating state. This is typically due to the fact that the APIService resource still exists however the webhook is no longer running so is no longer reachable. To resolve this, ensure you have run the above commands correctly, and if you're still experiencing issues then run:

kubectl delete apiservice v1beta1.webhook.cert-manager.io

Using the Flux Helm Controller

The cert-manager Helm chart can be installed and upgraded by the Flux Helm Controller.

📖 Read more at Continuous Deployment: Using the Flux Helm Controller.