// as the clusterIP.
  // "ExternalName" aliases this service to the specified externalName.
  // Several other fields do not apply to ExternalName services.
  // More info: https://kubernetes.io/docs/concepts/services-networking/service/#publishing-services-service-types
  // +optional
  optional string type = 4;

- Certain fields on  Service objects will be automatically cleared when changing the service's `type` to a mode that does not need those fields.  For example, changing...

* Cluster federation servers have changed the location in etcd where federated services are stored, so existing federated services must be deleted and recreated. Before upgrading, export all federated services from the federation server and delete the services. After upgrading the cluster, recreate the federated services from the exported data. ([#37770](https://github.com/kubernetes/kubernetes/pull/37770), [@enj](https://github.com/enj))

- the IP allocator in v1.17.0 can return errors such as `the cluster IP <ip> for service <service-name> is not within the service CIDR <cidr>; please recreate` in the logs of the kube-apiserver. The cause is incorrect CIDR calculations if the service CIDR (`--service-cluster-ip-range`) is set to bits lower than `/16`. This is fixed in http://issue.k8s.io/86534 and will be resolved in v1.17.1.

* A new service annotation has been added for services of type LoadBalancer on Azure,  ([#51757](https://github.com/kubernetes/kubernetes/pull/51757), [@itowlson](https://github.com/itowlson))
    * to specify the subnet on which the service's front end IP should be provisioned. The
    * annotation is service.beta.kubernetes.io/azure-load-balancer-internal-subnet and its

- Added validation to ensure that if `service.kubernetes.io/topology-aware-hints` and `service.kubernetes.io/topology-mode` annotations are both set, they are set to the same value.Also Added deprecation warning if `service.kubernetes.io/topology-aware-hints` annotation is used. ([#116612](https://github.com/kubernetes/kubernetes/pull/116612), [@robscott](https://github.com/robscott))...

    * Two api fields are defined correspondingly:
        * Service.Spec.ExternalTrafficPolicy <- 'service.beta.kubernetes.io/external-traffic' annotation.
        * Service.Spec.HealthCheckNodePort <- 'service.beta.kubernetes.io/healthcheck-nodeport' annotation.

### Avoiding Collisions in IP allocation to Services

Kubernetes 1.24 introduced a new opt-in feature that allows you to
[soft-reserve a range for static IP address assignments](https://kubernetes.io/docs/concepts/services-networking/service/#service-ip-static-sub-range)
to Services.
With the manual enablement of this feature, the cluster will prefer automatic assignment from
the pool of Service IP addresses thereby reducing the risk of collision.

[@caesarxuchao](https://github.com/caesarxuchao))

* Using kubectl gcp auth plugin with a Google Service Account to authenticate to a cluster now additionally requests a token with the  "userinfo.email" scope. This way, users can write ClusterRoleBindings/RoleBindings with the email address of the service account directly. (This is a breaking change if the numeric uniqueIDs of the Google service accounts were being used in RBAC role bindings. The behavior can be overridden by explicitly specifying...

- The conformance tests:
  - Services should serve multiport endpoints from pods
  - Services should serve a basic endpoint from pods
  were only validating the API objects, not performing any validation on the actual Services implementation.