// +optional
  optional int32 fullyLabeledReplicas = 2;

  // The number of ready replicas for this replication controller.
  // +optional
  optional int32 readyReplicas = 4;

  // The number of available replicas (ready for at least minReadySeconds) for this replication controller.
  // +optional

stable version in place and gradually migrate apps to the new version.

- More flexibility: the new installer allows multiple 'environments', allowing applications to select
a set of control plane settings and components. While the entire mesh respects the same APIs and config,
apps may target different 'environments' which contain different instances and variants of Istio.

  // 128 characters long, and only contain printable characters,
  // as defined by https://golang.org/pkg/unicode/#IsPrint. This
  // field is required for apply requests
  // (application/apply-patch) but optional for non-apply patch
  // types (JsonPatch, MergePatch, StrategicMergePatch).
  // +optional
  optional string fieldManager = 3;

  // fieldValidation instructs the server on how to handle

   policy enforcement and telemetry recording/reporting
   functions.

  > Note: The service mesh is not an overlay network. It
  > simplifies and enhances how microservices in an application talk to each
  > other over the network provided by the underlying platform.

# Port and basic host configuration

In order to configure the Service object, the install/upgrade needs to provide a list of all ports.
In the past, this was done when installing/upgrading full istio, and involved some duplication - ports configured
both in upgrade, Gateway and VirtualService.

The new Ingress chart uses a 'values.yaml' (see user-example-ingress), which auto-generates Service ports,

|PROV_CERT|certificates to be used for mTLS communication with control plane only; NOT for workload mTLS|
|OUTPUT_CERT|write all fetched certificates to some directory. Used to support applications that need certificates (Prometheus) as well as rotating mTLS control plane authentication.|
|FILE_MOUNTED_CERTS|completely disable CA path, exclusively use certs mounted into the pod with set certificate file locations|

replicaCount | [replica count](https://kubernetes.io/docs/concepts/workloads/controllers/deployment/)
hpaSpec | [HorizontalPodAutoscaler](https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale/)
podDisruptionBudget | [PodDisruptionBudget](https://kubernetes.io/docs/concepts/workloads/pods/disruptions/#how-disruption-budgets-work)

  // which corresponds to the IfHealthyBudget policy.
  //
  // IfHealthyBudget policy means that running pods (status.phase="Running"),
  // but not yet healthy can be evicted only if the guarded application is not
  // disrupted (status.currentHealthy is at least equal to status.desiredHealthy).
  // Healthy pods will be subject to the PDB for eviction.
  //

     of liability) contained within the Source Code Form of the Covered
     Software, except that You may alter any license notices to the extent
     required to remedy known factual inaccuracies.

3.5. Application of Additional Terms

     You may choose to offer, and to charge a fee for, warranty, support,
     indemnity or liability obligations to one or more recipients of Covered