Add page listing removed beta versions and notable changes

Author: liggitt

content/en/docs/reference/using-api/deprecation-guide.md

@@ -0,0 +1,265 @@
+---
+reviewers:
+- liggitt
+- lavalamp
+- thockin
+- smarterclayton
+title: "Deprecated API Migration Guide"
+weight: 45
+content_type: api_reference
+---
+
+<!-- overview -->
+
+As the Kubernetes API evolves, APIs are periodically reorganized or upgraded.
+When APIs evolve, the old API is deprecated and eventually removed.
+This page contains information you need to know when migrating from
+deprecated API versions to newer and more stable API versions.
+
+<!-- body -->
+
+## Removed APIs by release
+
+
+### v1.25
+
+The **v1.25** release will stop serving the following deprecated API versions:
+
+#### Event
+
+The **events.k8s.io/v1beta1** API version of Event will no longer be served in v1.25.
+
+* Migrate manifests and API clients to use the **events.k8s.io/v1** API version, available since v1.19.
+* All existing persisted objects are accessible via the new API
+* Notable changes
+
+#### RuntimeClass
+
+RuntimeClass in the **node.k8s.io/v1beta1** API version will no longer be served in v1.25.
+
+* Migrate manifests and API clients to use the **node.k8s.io/v1** API version, available since v1.20.
+* All existing persisted objects are accessible via the new API
+* No notable changes
+
+### v1.22
+
+The **v1.22** release will stop serving the following deprecated API versions:
+
+#### MutatingWebhookConfiguration and ValidatingWebhookConfiguration
+
+The **admissionregistration.k8s.io/v1beta1** API version of MutatingWebhookConfiguration and ValidatingWebhookConfiguration will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **admissionregistration.k8s.io/v1** API version, available since v1.16.
+* All existing persisted objects are accessible via the new API
+* Notable changes:
+    * `webhooks[*].failurePolicy` default changed from `Ignore` to `Fail` for v1
+    * `webhooks[*].matchPolicy` default changed from `Exact` to `Equivalent` for v1
+    * `webhooks[*].timeoutSeconds` default changed from `30s` to `10s` for v1
+    * `webhooks[*].sideEffects` default value is removed, and the field made required, and only `None` and `NoneOnDryRun` are permitted for v1
+    * `webhooks[*].admissionReviewVersions` default value is removed and the field made required for v1 (supported versions for AdmissionReview are `v1` and `v1beta1`)
+    * `webhooks[*].name` must be unique in the list for objects created via `admissionregistration.k8s.io/v1`
+
+#### CustomResourceDefinitions
+
+The **apiextensions.k8s.io/v1beta1** API version of CustomResourceDefinition will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **apiextensions.k8s.io/v1beta1** API version, available since v1.16.
+* All existing persisted objects are accessible via the new API
+* Notable changes:
+    * `spec.scope` is no longer defaulted to `Namespaced` and must be explicitly specified
+    * `spec.version` is removed in v1; use `spec.versions` instead
+    * `spec.validation` is removed in v1; use `spec.versions[*].schema` instead
+    * `spec.subresources` is removed in v1; use `spec.versions[*].subresources` instead
+    * `spec.additionalPrinterColumns` is removed in v1; use `spec.versions[*].additionalPrinterColumns` instead
+    * `spec.conversion.webhookClientConfig` is moved to `spec.conversion.webhook.clientConfig` in v1
+    * `spec.conversion.conversionReviewVersions` is moved to `spec.conversion.webhook.conversionReviewVersions` in v1
+    * `spec.versions[*].schema.openAPIV3Schema` is now required when creating v1 CustomResourceDefinitions, and must be a [structural schema](/docs/tasks/extend-kubernetes/custom-resources/custom-resource-definitions/#specifying-a-structural-schema)
+    * `spec.preserveUnknownFields: true` is disallowed when creating v1 CustomResourceDefinitions; it must be specified within schema definitions as `x-kubernetes-preserve-unknown-fields: true`
+    * In `additionalPrinterColumns` items, the `JSONPath` field was renamed to `jsonPath` in v1 (fixes [#66531](https://github.com/kubernetes/kubernetes/issues/66531))
+
+#### APIService
+
+The **apiregistration.k8s.io/v1beta1** API version of APIService will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **apiregistration.k8s.io/v1** API version, available since v1.10.
+* All existing persisted objects are accessible via the new API
+* No notable changes
+
+#### TokenReview
+
+The **authentication.k8s.io/v1beta1** API version of TokenReview will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **authentication.k8s.io/v1** API version, available since v1.6.
+* No notable changes
+
+#### SubjectAccessReview
+
+The **authorization.k8s.io/v1beta1** API version of LocalSubjectAccessReview, SelfSubjectAccessReview, and SubjectAccessReview will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **authorization.k8s.io/v1** API version, available since v1.6.
+* Notable changes:
+    * `spec.group` was renamed to `spec.groups` in v1 (fixes [#32709](https://github.com/kubernetes/kubernetes/issues/32709))
+
+#### CertificateSigningRequest
+
+The **certificates.k8s.io/v1beta1** API version of CertificateSigningRequest will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **certificates.k8s.io/v1** API version, available since v1.19.
+* All existing persisted objects are accessible via the new API
+* Notable changes in `certificates.k8s.io/v1`:
+    * For API clients requesting certificates:
+        * `spec.signerName` is now required (see [known Kubernetes signers](https://kubernetes.io/docs/reference/access-authn-authz/certificate-signing-requests/#kubernetes-signers)), and requests for `kubernetes.io/legacy-unknown` are not allowed to be created via the `certificates.k8s.io/v1` API
+        * `spec.usages` is now required, may not contain duplicate values, and must only contain known usages
+    * For API clients approving or signing certificates:
+        * `status.conditions` may not contain duplicate types
+        * `status.conditions[*].status` is now required
+        * `status.certificate` must be PEM-encoded, and contain only `CERTIFICATE` blocks
+
+#### Lease
+
+The **coordination.k8s.io/v1beta1** API version of Lease will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **coordination.k8s.io/v1** API version, available since v1.14.
+* All existing persisted objects are accessible via the new API
+* No notable changes
+
+#### Ingress
+
+The **extensions/v1beta1** and **networking.k8s.io/v1beta1** API versions of Ingress will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **networking.k8s.io/v1** API version, available since v1.19.
+* All existing persisted objects are accessible via the new API
+* Notable changes:
+    * `spec.backend` is renamed to `spec.defaultBackend`
+    * The backend `serviceName` field is renamed to `service.name`
+    * Numeric backend `servicePort` fields are renamed to `service.port.number`
+    * String backend `servicePort` fields are renamed to `service.port.name`
+    * `pathType` is now required for each specified path. Options are `Prefix`, `Exact`, and `ImplementationSpecific`. To match the undefined `v1beta1` behavior, use `ImplementationSpecific`.
+
+#### IngressClass
+
+The **networking.k8s.io/v1beta1** API version of IngressClass will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **networking.k8s.io/v1** API version, available since v1.19.
+* All existing persisted objects are accessible via the new API
+* No notable changes
+
+#### RBAC
+
+The **rbac.authorization.k8s.io/v1beta1** API version of ClusterRole, ClusterRoleBinding, Role, and RoleBinding will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **networking.k8s.io/v1** API version, available since v1.8.
+* All existing persisted objects are accessible via the new API
+* No notable changes
+
+#### PriorityClass
+
+The **scheduling.k8s.io/v1beta1** API version of PriorityClass will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **scheduling.k8s.io/v1** API version, available since v1.14.
+* All existing persisted objects are accessible via the new API
+* No notable changes
+
+#### Storage
+
+The **storage.k8s.io/v1beta1** API version of CSIDriver, CSINode, StorageClass, and VolumeAttachment will no longer be served in v1.22.
+
+* Migrate manifests and API clients to use the **storage.k8s.io/v1** API version
+  * CSIDriver is available in **storage.k8s.io/v1** since v1.19.
+  * CSINode is available in **storage.k8s.io/v1** since v1.17
+  * StorageClass is available in **storage.k8s.io/v1** since v1.6
+  * VolumeAttachment is available in **storage.k8s.io/v1** v1.13
+* All existing persisted objects are accessible via the new API
+* No notable changes
+
+### v1.16
+
+The **v1.16** release stopped serving the following deprecated API versions:
+
+#### NetworkPolicy
+
+The **extensions/v1beta1** API version of NetworkPolicy is no longer served as of v1.16.
+
+* Migrate manifests and API clients to use the **networking.k8s.io/v1** API version, available since v1.8.
+* All existing persisted objects are accessible via the new API
+
+#### DaemonSet
+
+The **extensions/v1beta1** and **apps/v1beta2** API versions of DaemonSet are no longer served as of v1.16.
+
+* Migrate manifests and API clients to use the **apps/v1** API version, available since v1.9.
+* All existing persisted objects are accessible via the new API
+* Notable changes:
+    * `spec.templateGeneration` is removed
+    * `spec.selector` is now required and immutable after creation; use the existing template labels as the selector for seamless upgrades
+    * `spec.updateStrategy.type` now defaults to `RollingUpdate` (the default in `extensions/v1beta1` was `OnDelete`)
+
+#### Deployment
+
+The **extensions/v1beta1**, **apps/v1beta1**, and **apps/v1beta2** API versions of Deployment are no longer served as of v1.16.
+
+* Migrate manifests and API clients to use the **apps/v1** API version, available since v1.9.
+* All existing persisted objects are accessible via the new API
+* Notable changes:
+    * `spec.rollbackTo` is removed
+    * `spec.selector` is now required and immutable after creation; use the existing template labels as the selector for seamless upgrades
+    * `spec.progressDeadlineSeconds` now defaults to `600` seconds (the default in `extensions/v1beta1` was no deadline)
+    * `spec.revisionHistoryLimit` now defaults to `10` (the default in `apps/v1beta1` was `2`, the default in `extensions/v1beta1` was to retain all)
+    * `maxSurge` and `maxUnavailable` now default to `25%` (the default in `extensions/v1beta1` was `1`)
+
+#### StatefulSet
+
+The **apps/v1beta1** and **apps/v1beta2** API versions of StatefulSet are no longer served as of v1.16.
+
+* Migrate manifests and API clients to use the **apps/v1** API version, available since v1.9.
+* All existing persisted objects are accessible via the new API
+* Notable changes:
+    * `spec.selector` is now required and immutable after creation; use the existing template labels as the selector for seamless upgrades
+    * `spec.updateStrategy.type` now defaults to `RollingUpdate` (the default in `apps/v1beta1` was `OnDelete`)
+
+#### ReplicaSet
+
+The **extensions/v1beta1**, **apps/v1beta1**, and **apps/v1beta2** API versions of ReplicaSet are no longer served as of v1.16.
+
+* Migrate manifests and API clients to use the **apps/v1** API version, available since v1.9.
+* All existing persisted objects are accessible via the new API
+* Notable changes:
+    * `spec.selector` is now required and immutable after creation; use the existing template labels as the selector for seamless upgrades
+
+## What To Do
+
+Kubernetes 1.22 will be released later in 2021, so be sure to audit
+your configuration and integrations now!
+
+### Test with deprecated APIs disabled
+
+You can test your clusters by starting an API server with specific API versions disabled
+to simulate upcoming removals. Add the following flag to the API server startup arguments:
+
+`--runtime-config=$group/$version=false`
+
+For example:
+
+`--runtime-config=admissionregistration.k8s.io/v1beta1=false,apiextensions.k8s.io/v1beta1,...`
+
+### Locate use of deprecated APIs
+
+Use [client warnings, metrics, and audit information available in 1.19+](https://kubernetes.io/blog/2020/09/03/warnings/#deprecation-warnings)
+to locate use of deprecated APIs.
+
+### Migrate to non-deprecated APIs
+
+* Update custom integrations and controllers to call the non-deprecated APIs
+* Change YAML files to reference the non-deprecated APIs
+
+    You can use the `kubectl-convert` command (`kubectl convert` prior to v1.20)
+    to automatically convert an existing object:
+    
+    `kubectl-convert -f <file> --output-version <group>/<version>`.
+
+    For example, to convert an older Deployment to `apps/v1`, you can run:
+    
+    `kubectl-convert -f ./my-deployment.yaml --output-version apps/v1`
+
+    Note that this may use non-ideal default values. To learn more about a specific
+    resource, check the Kubernetes [api reference](https://kubernetes.io/docs/reference/#api-reference).