Uninstalling the Operator

How to uninstall the Altinity Kubernetes Operator for ClickHouse®

To remove the Altinity Kubernetes Operator for ClickHouse®, both the operator and the components in its installed namespace will have to be removed. The proper command is to uses the same clickhouse-operator-install-bundle.yaml file that was used to install the operator. See the [installation instructions] for more information.

The following instructions are based on the standard installation instructions. For users who perform a [custom installation], note that the any custom namespaces that the user wants to remove will have to be deleted separate from the operator deletion.

For example, if the custom namespace operator-test is created, then it would be removed with the command kubectl delete namespaces operator-test.

IMPORTANT NOTICE 1

Never delete the operator or run the following command while there are live ClickHouse clusters managed by the operator:

kubectl delete --namespace "kube-system" -f https://github.com/Altinity/clickhouse-operator/raw/0.24.5/deploy/operator/clickhouse-operator-install-bundle.yaml

The command will hang due to the live clusters. If you then re-install the operator, those clusters will be deleted and the operator will not work correctly.

See Issue #830 in the Altinity/clickhouse-operator repo for more details.

IMPORTANT NOTICE 2

Please follow the instructions below. The uninstall command is geared to properly remove the operator and its namespace. Deleting the namespace without properly removing the operator can cause it to hang.

Instructions

To remove the operator from your Kubernetes environment from a standard install:

Verify the operator is in the kube-system namespace. The operators pods and other pods will be displayed:

NAME                                   READY   STATUS    RESTARTS      AGE
clickhouse-operator-857c69ffc6-2frgl   2/2     Running   0             5s
coredns-78fcd69978-nthp2               1/1     Running   4 (23h ago)   51d
etcd-minikube                          1/1     Running   4 (23h ago)   51d
kube-apiserver-minikube                1/1     Running   4 (23h ago)   51d
kube-controller-manager-minikube       1/1     Running   4 (23h ago)   51d
kube-proxy-lsggn                       1/1     Running   4 (23h ago)   51d
kube-scheduler-minikube                1/1     Running   4 (23h ago)   51d
storage-provisioner                    1/1     Running   9 (23h ago)   51d

Issue the kubectl delete command using the same YAML file used to install the operator. By default the operator is installed in the namespace kube-system. If this was installed into a custom namespace, verify that it installed in the uninstall command. In this example, we specified an installation of the operator version 0.24.5 into the default kube-system namespace. This produces output similar to the following:

kubectl delete -f https://github.com/Altinity/clickhouse-operator/raw/0.24.5/deploy/operator/clickhouse-operator-install-bundle.yaml

customresourcedefinition.apiextensions.k8s.io "clickhouseinstallations.clickhouse.altinity.com" deleted
customresourcedefinition.apiextensions.k8s.io "clickhouseinstallationtemplates.clickhouse.altinity.com" deleted
customresourcedefinition.apiextensions.k8s.io "clickhouseoperatorconfigurations.clickhouse.altinity.com" deleted
serviceaccount "clickhouse-operator" deleted
clusterrole.rbac.authorization.k8s.io "clickhouse-operator-kube-system" deleted
clusterrolebinding.rbac.authorization.k8s.io "clickhouse-operator-kube-system" deleted
configmap "etc-clickhouse-operator-files" deleted
configmap "etc-clickhouse-operator-confd-files" deleted
configmap "etc-clickhouse-operator-configd-files" deleted
configmap "etc-clickhouse-operator-templatesd-files" deleted
configmap "etc-clickhouse-operator-usersd-files" deleted
deployment.apps "clickhouse-operator" deleted
service "clickhouse-operator-metrics" deleted

To verify the operator has been removed, use the kubectl get namespaces command:

kubectl get pods --namespace kube-system

NAME                               READY   STATUS    RESTARTS      AGE
coredns-78fcd69978-nthp2           1/1     Running   4 (23h ago)   51d
etcd-minikube                      1/1     Running   4 (23h ago)   51d
kube-apiserver-minikube            1/1     Running   4 (23h ago)   51d
kube-controller-manager-minikube   1/1     Running   4 (23h ago)   51d
kube-proxy-lsggn                   1/1     Running   4 (23h ago)   51d
kube-scheduler-minikube            1/1     Running   4 (23h ago)   51d
storage-provisioner                1/1     Running   9 (23h ago)   51d