MOCO Helm Chart

How to use MOCO Helm repository

You need to add this repository to your Helm repositories:

$ helm repo add moco https://cybozu-go.github.io/moco/
$ helm repo update

Quick start

Installing cert-manager

$ curl -fsL https://github.com/jetstack/cert-manager/releases/latest/download/cert-manager.yaml | kubectl apply -f -

Installing the Chart

NOTE:

This installation method requires cert-manager to be installed beforehand. To install the chart with the release name moco using a dedicated namespace(recommended):

$ helm install --create-namespace --namespace moco-system moco moco/moco

Specify parameters using --set key=value[,key=value] argument to helm install.

Alternatively a YAML file that specifies the values for the parameters can be provided like this:

$ helm install --create-namespace --namespace moco-system moco -f values.yaml moco/moco

Values

Key	Type	Default	Description
replicaCount	number	`2`	Number of controller replicas.
image.repository	string	`"ghcr.io/cybozu-go/moco"`	MOCO image repository to use.
image.pullPolicy	string	`IfNotPresent`	MOCO image pulling policy.
image.tag	string	`{{ .Chart.AppVersion }}`	MOCO image tag to use.
imagePullSecrets	list	`[]`	Secrets for pulling MOCO image from private repository.
resources	object	`{"requests":{"cpu":"100m","memory":"20Mi"}}`	resources used by moco-controller.
crds.enabled	bool	`true`	Install and update CRDs as part of the Helm chart.
extraArgs	list	`[]`	Additional command line flags to pass to moco-controller binary.
nodeSelector	object	`{}`	nodeSelector used by moco-controller.
affinity	object	`{}`	affinity used by moco-controller.
tolerations	list	`[]`	tolerations used by moco-controller.
topologySpreadConstraints	list	`[]`	topologySpreadConstraints used by moco-controller.
priorityClassName	string	`""`	PriorityClass used by moco-controller.

Generate Manifests

You can use the helm template command to render manifests.

$ helm template --namespace moco-system moco moco/moco

CRD considerations

Installing or updating CRDs

MOCO Helm Chart installs or updates CRDs by default. If you want to manage CRDs on your own, turn off the crds.enabled parameter.

Removing CRDs

Helm does not remove the CRDs due to the helm.sh/resource-policy: keep annotation. When uninstalling, please remove the CRDs manually.

Migrate to v0.11.0 or higher

Chart version v0.11.0 introduces the crds.enabled parameter.

When updating to a new chart from chart v0.10.x or lower, you MUST leave this parameter true (the default value). If you turn off this option when updating, the CRD will be removed, causing data loss.

Migrate to v0.3.0

Chart version v0.3.0 has breaking changes. The .metadata.name of the resource generated by Chart is changed.

e.g.

{{ template "moco.fullname" . }}-foo-resources -> moco-foo-resources

Related Issue: cybozu-go/moco#426

If you are using a release name other than moco, you need to migrate.

The migration steps involve deleting and recreating each MOCO resource once, except CRDs. Since the CRDs are not deleted, the pods running existing MySQL clusters are not deleted, so there is no downtime. However, the migration process should be completed in a short time since the moco-controller will be temporarily deleted and no control over the cluster will be available.

migration steps

Show the installed chart

$ helm list -n <YOUR NAMESPACE>
NAME    NAMESPACE       REVISION        UPDATED                                 STATUS          CHART           APP VERSION
moco    moco-system     1               2022-08-17 11:28:23.418752 +0900 JST    deployed        moco-0.2.3      0.12.1

Render the manifests

$ helm template --namespace moco-system --version <YOUR CHART VERSION> <YOUR INSTALL NAME> moco/moco > render.yaml

Setup kustomize

$ cat > kustomization.yaml <<'EOF'
resources:
  - render.yaml
patches:
  - crd-patch.yaml
EOF

$ cat > crd-patch.yaml <<'EOF'
$patch: delete
apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
  name: backuppolicies.moco.cybozu.com
---
$patch: delete
apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
  name: mysqlclusters.moco.cybozu.com
EOF

Delete resources

$ kustomize build ./ | kubectl delete -f -
serviceaccount "moco-controller-manager" deleted
role.rbac.authorization.k8s.io "moco-leader-election-role" deleted
clusterrole.rbac.authorization.k8s.io "moco-backuppolicy-editor-role" deleted
clusterrole.rbac.authorization.k8s.io "moco-backuppolicy-viewer-role" deleted
clusterrole.rbac.authorization.k8s.io "moco-manager-role" deleted
clusterrole.rbac.authorization.k8s.io "moco-mysqlcluster-editor-role" deleted
clusterrole.rbac.authorization.k8s.io "moco-mysqlcluster-viewer-role" deleted
rolebinding.rbac.authorization.k8s.io "moco-leader-election-rolebinding" deleted
clusterrolebinding.rbac.authorization.k8s.io "moco-manager-rolebinding" deleted
service "moco-webhook-service" deleted
deployment.apps "moco-controller" deleted
certificate.cert-manager.io "moco-controller-grpc" deleted
certificate.cert-manager.io "moco-grpc-ca" deleted
certificate.cert-manager.io "moco-serving-cert" deleted
issuer.cert-manager.io "moco-grpc-issuer" deleted
issuer.cert-manager.io "moco-selfsigned-issuer" deleted
mutatingwebhookconfiguration.admissionregistration.k8s.io "moco-mutating-webhook-configuration" deleted
validatingwebhookconfiguration.admissionregistration.k8s.io "moco-validating-webhook-configuration" deleted

Delete Secret

$ kubectl delete secret sh.helm.release.v1.<YOUR INSTALL NAME>.v1 -n <YOUR NAMESPACE>

Re-install the v0.3.0 chart

$ helm install --create-namespace --namespace moco-system --version 0.3.0 moco moco/moco

Release Chart

See RELEASE.md.

MOCO Documentation