Kubectl apply

Installing with regular manifests

Prerequisites

• Install kubectl version >= v1.19.0. (otherwise, you will have issues updating the CRDs - see v0.16 upgrade notes)
• Install a supported version of Kubernetes or OpenShift.
• Read Compatibility with Kubernetes Platform Providers if you are using Kubernetes on a cloud platform.

Steps

All resources (the CustomResourceDefinitions and the cert-manager, cainjector and webhook components) are included in a single YAML manifest file:

Install all cert-manager components:

kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/v1.8.2/cert-manager.yaml

By default, cert-manager will be installed into the cert-manager namespace. It is possible to run cert-manager in a different namespace, although you'll need to make modifications to the deployment manifests.

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

Permissions Errors on Google Kubernetes Engine

When running on GKE (Google Kubernetes Engine), you might encounter a 'permission denied' error when creating some of the required resources. This is a nuance of the way GKE handles RBAC and IAM permissions, and as such you might need to elevate your own privileges to that of a "cluster-admin" before running kubectl apply.

If you have already run kubectl apply, you should run it again after elevating your permissions:

$ kubectl create clusterrolebinding cluster-admin-binding \
    --clusterrole=cluster-admin \
    --user=$(gcloud config get-value core/account)

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 regular manifests

Uninstalling from an installation with regular manifests is a case of running the installation process, in reverse, using the delete command of kubectl.

Delete the installation manifests using a link to your currently running version vX.Y.Z like so:

Warning: This command will also remove installed cert-manager CRDs. All cert-manager resources (e.g. certificates.cert-manager.io resources) will be removed by Kubernetes' garbage collector.

$ kubectl delete -f https://github.com/cert-manager/cert-manager/releases/download/vX.Y.Z/cert-manager.yaml

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