}
			ns := ctx.NamespaceOrDefault(ctx.Namespace())
			// If a user decides to enroll their namespace with a waypoint, verify that they have labeled their namespace as ambient.
			// If they don't, the user will be warned and be presented with the command to label their namespace as ambient if they
			// choose to do so.
			//
			// NOTE: This is a warning and not an error because the user may not intend to label their namespace as ambient.
			//

    CZ--"HBONE (actual)"-->SZ
    SZ--Plain-->Server
```

### Pooling

User connections can be multiplexed over shared HBONE connections.
This is done through standard HTTP/2 pooling.
The pooling is keyed off the `{source identity, destination identity, destination ip}`.

### Headers

Ztunnel uses the following well-known headers in HBONE:

    #
    # Then starting a pod with the `inject.istio.io/templates: hello` annotation, will result in the pod
    # being injected with the hello=world labels.
    # This is intended for advanced configuration only; most users should use the built in template
    templates: {}

    # Default templates specifies a set of default templates that are used in sidecar injection.

	// This will get a network namespace ID. This ID is scoped to the network namespace we running in.
	// As such, we need to be in the host namespace: the CNI pod namespace has no relation to the users pod namespace.
	netns, err := runInHost(func() (string, error) { return getPodNetNs(pod) })
	if err != nil {
		m.With(resultLabel.Value(resultFail)).Increment()
		return fmt.Errorf("get netns: %v", err)
	}

  // a URL. You may use the path to pass an arbitrary string to the
  // webhook, for example, a cluster identifier.
  //
  // Attempting to use a user or basic auth e.g. "user:password@" is not
  // allowed. Fragments ("#...") and query parameters ("?...") are not
  // allowed, either.
  //
  // +optional
  optional string url = 3;

  // User is the user you're testing for.
  // If you specify "User" but not "Group", then is it interpreted as "What if User were not a member of any groups
  // +optional
  optional string user = 3;

  // Groups is the groups you're testing for.
  // +optional
  repeated string group = 4;

  // a URL. You may use the path to pass an arbitrary string to the
  // webhook, for example, a cluster identifier.
  //
  // Attempting to use a user or basic auth e.g. "user:password@" is not
  // allowed. Fragments ("#...") and query parameters ("?...") are not
  // allowed, either.
  //
  // +optional
  optional string url = 3;

- In ambient mode, the CNI plugin does not configure any networking, but is only responsible for synchronously pushing new pod events back up to an ambient watch server which runs as part of the Istio CNI node agent. The ambient...

  // User is the user you're testing for.
  // If you specify "User" but not "Groups", then is it interpreted as "What if User were not a member of any groups
  // +optional
  optional string user = 3;

  // Groups is the groups you're testing for.
  // +optional
  repeated string groups = 4;

	return fmt.Sprintf("no running Istio pods in %q", c.Namespace)
}

var _ error = ControlPlaneNotFoundError{}

type Options struct {
	// MessageWriter is a writer for displaying messages to users.
	MessageWriter io.Writer

	// XdsViaAgents accesses Istiod via the tap service of each agent.
	// This is only used in `proxy-status` command.
	XdsViaAgents bool