snapshot-validation-webhook

snapshot-validation-webhook

Deploys the snapshot-validation-webhook and configures your cluster to validate every VolumeSnapshot and VolumeSnapshotContent resource by sending it to the webhook.

This webhook should be deployed on all clusters that are using the snapshot-controller chart, or are in the process of installing it.

Usage

The following commands install this chart in your cluster. See below for available configuration options.

helm repo add piraeus-charts https://piraeus.io/helm-charts/
helm install snapshot-validation-webhook piraeus-charts/snapshot-validation-webhook

Upgrades

Upgrades can be done using the normal Helm upgrade mechanism

helm repo update
helm upgrade snapshot-validation-webhook piraeus-charts/snapshot-validation-webhook

Upgrade from older CRDs

In an effort to tighten validation, the CSI project started enforcing stricter requirements on VolumeSnapshot and VolumeSnapshotContent resources when switching from v1beta1 to v1 CRDs. This webhook is part of enforcing these requirements. When upgrading you have to ensure non of your resources violate the requirements for v1.

The upgrade procedure can be summarized by the following steps:

1. Remove the old snapshot controller, if any (since you are upgrading, you probably already have one deployed manually).

2. Install this webhook chart.

3. Install the snapshot controller using one of the 3.x.x releases:

   helm install piraeus-charts/snapshot-controller --set image.tag=v3.0.3
   

4. Ensure that none of the resources are labelled as invalid:

   kubectl get volumesnapshots --selector=snapshot.storage.kubernetes.io/invalid-snapshot-resource="" --all-namespaces
   kubectl get volumesnapshotcontents --selector=snapshot.storage.kubernetes.io/invalid-snapshot-resource="" --all-namespaces
   

   If the above commands output any resource, they have to be removed

5. Upgrade the CRDs

   kubectl replace -f https://raw.githubusercontent.com/kubernetes-csi/external-snapshotter/v5.0.0/client/config/crd/snapshot.storage.k8s.io_volumesnapshotclasses.yaml
   kubectl replace -f https://raw.githubusercontent.com/kubernetes-csi/external-snapshotter/v5.0.0/client/config/crd/snapshot.storage.k8s.io_volumesnapshots.yaml
   kubectl replace -f https://raw.githubusercontent.com/kubernetes-csi/external-snapshotter/v5.0.0/client/config/crd/snapshot.storage.k8s.io_volumesnapshotcontents.yaml
   

6. Upgrade the snapshot controller to the latest version:

   helm upgrade piraeus-charts/snapshot-controller --set image.tag=v5.0.0
   

Configuration

Webhooks in Kubernetes are required to run on HTTPS. To that end, this charts needs to be configured with one of the following options:

• An auto-generated certificate, valid for 10 years. This is the default. If you want to renew the certificate, set tls.renew to true and run an upgrade.

• A cert-manager.io issuer able to create a certificate for the webhook service.

  To use this method, create an override file like:

  tls:
    certManagerIssuerRef:
      name: internal-issuer
      kind: ClusterIssuer
  

  To apply the override, use --values <override-file>.

• A pre-existing kubernetes.io/tls secret and the certificate of the CA used to sign said tls secret.

  To use this method, set --set tls.certificateSecret=<secretname>. The secret must be in the same namespace as the deployment and be valid for <release-name>.<namespace>.svc.

There are additional options that allow customization outside of HTTPS concerns. This is the full list of options available.

Option	Usage	Default
args	Arguments to pass to the snapshot controller. Note: Keys will be converted to kebab-case, i.e. oneArg -> --one-arg	...
replicaCount	Number of replicas to deploy.	1
image.repository	Repository to pull the image from.	registry.k8s.io/sig-storage/snapshot-validation-webhook
image.pullPolicy	Pull policy to use. Possible values: IfNotPresent, Always, Never	IfNotPresent
image.tag	Override the tag to pull. If not given, defaults to charts AppVersion.	""
webhook.timeoutSeconds	Timeout to use when contacting webhook server.	2
webhook.failurePolicy	Policy to apply when webhook is unavailable. Possible values: Fail, Ignore.	Fail
tls.certificateSecret	Name of the static tls secret to use for serving the HTTPS endpoint.	""
tls.autogenerate	Automatically generate the TLS secret for serving the HTTPS endpoint.	true
tls.renew	Force renewal of certificate when auto-generating.	false
tls.certManagerIssuerRef	Issuer to use for provisioning the TLS certificate. If this is used, tls.certificateSecret can be left empty.	{}
imagePullSecrets	Image pull secrets to add to the deployment.	[]
podAnnotations	Annotations to add to every pod in the deployment.	{}
networkPolicy.enabled	Should a network policy be created.	false
networkPolicy.ingress	Additional ingress rules to be added to the network policy.	{}
podDisruptionBudget.enabled	Should a pod disruption budget be created.	false
podDisruptionBudget.maxUnavailable	The maximum number of pods that are allowed to be unavailable.	""
podDisruptionBudget.minAvailable	The minimum number of pods that are required to be available.	""
priorityClassName	The name of the priority class to assign to the deployment.	""
topologySpreadConstraints	A list of topology constraints to assign to the deployment.	[]
podSecurityContext	Security context to set on the webhook pod.	{}
securityContext	Configure container security context. Defaults to dropping all capabilties and running as user 1000.	{capabilities: {drop: [ALL]}, readOnlyRootFilesystem: true, runAsNonRoot: true, runAsUser: 1000}
resources	Resources to request and limit on the pod.	{}
nodeSelector	Node selector to add to each webhook pod.	{}
tolerations	Tolerations to add to each webhook pod.	[]
affinity	Affinity to set on each webhook pod.	{}
serviceAccount.create	Create the service account resource	true
serviceAccount.name	Sets the name of the service account. If left empty, will use the release name as default	""