workloads can talk with each other and obey the Istio configuration resources, but each environment
can use different Istio versions and different configuration defaults.

`istioctl kube-inject` or the automatic sidecar injector are used to select the environment.
In the case of the sidecar injector, the namespace label `istio-env: <NAME_OF_ENV>` is used instead

- sends UDS events to ztunnel via a socket whenever a pod is enabled for ambient mesh (whether from CNI plugin or node watcher), instructing ztunnel to create the "tube" socket.

The ambient CNI agent is the only place where ambient network config and pod redirection machinery happens.

```console
helm install istio-cni istio/cni -n kube-system
```

Installation in `kube-system` is recommended to ensure the [`system-node-critical`](https://kubernetes.io/docs/tasks/administer-cluster/guaranteed-scheduling-critical-addon-pods/)
`priorityClassName` can be used. You can install in other namespace only on K8S clusters that allow
'system-node-critical' outside of kube-system.

## Configuration