If the change truly is generally purpose, it is generally preferred to have broader APIs. For example, instead of providing
direct access to each of the complex fields in [affinity](https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/), just providing
a single `affinity` field that is passed through as-is to the Kubernetes resource.
This provides maximum flexibility with minimal API surface overhead.

## Making changes

- [node selector](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#nodeselector)
- [toleration](https://kubernetes.io/docs/concepts/configuration/taint-and-toleration/)
- [affinity and anti-affinity](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity)
- [deployment strategy](https://kubernetes.io/docs/concepts/workloads/controllers/deployment/)

  // `scope-hostname.io/name`.
  // If empty, it will be defaulted:
  //  1. If it's a kubelet client certificate, it is assigned
  //     "kubernetes.io/kube-apiserver-client-kubelet".
  //  2. If it's a kubelet serving certificate, it is assigned
  //     "kubernetes.io/kubelet-serving".
  //  3. Otherwise, it is assigned "kubernetes.io/legacy-unknown".
  // Distribution of trust for signers happens out of band.

  optional StatefulSetPersistentVolumeClaimRetentionPolicy persistentVolumeClaimRetentionPolicy = 10;

  // ordinals controls the numbering of replica indices in a StatefulSet. The
  // default ordinals behavior assigns a "0" index to the first replica and
  // increments the index by one for each additional replica requested. Using
  // the ordinals field requires the StatefulSetStartOrdinal feature gate to be
  // enabled, which is beta.

## Reference

### Design details

Broadly, `istio-cni` accomplishes ambient redirection by instructing ztunnel to set up sockets within the application pod network namespace, where:

- one end of the socket is in the application pod

nodeSelector| [node selector](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#nodeselector)
affinity | [affinity and anti-affinity](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity)
serviceAnnotations | [service annotations](https://kubernetes.io/docs/concepts/overview/working-with-objects/annotations/)

* All changes should have an associated GitHub issue and/or a release note.
    * In the event that a bug cannot be automatically backported, the istio-testing bot creates an issue for a failed
    attempt and assigns it to the developer. This issue **is not** sufficient for requesting approval.
* For manual cherry-picks:
    * Large fixes, where the LOC>100 not withstanding unit tests changes, require subject-matter expert approval.

# Ztunnel

This document provides an overview of the architecture and design decisions around Ztunnel, the node-proxy component in ambient mode.

## Background and motivation

Motivations to implement ztunnel generally came from two areas.

First, and most importantly, it serves as a means to implement the real goal: waypoints.

  // controller. If a Job is suspended after creation (i.e. the flag goes from
  // false to true), the Job controller will delete all active Pods associated
  // with this Job. Users must design their workload to gracefully handle this.
  // Suspending a Job will reset the StartTime field of the Job, effectively
  // resetting the ActiveDeadlineSeconds timer too. Defaults to false.
  //
  // +optional

// used to indicate that an IngressClass should be considered default. When a
// single IngressClass resource has this annotation set to true, new Ingress
// resources without a class specified will be assigned this default class.
message IngressClass {
  // Standard object's metadata.
  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
  // +optional