- 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 server will find the pod netns and configure networking inside that pod via iptables. The ambient server will additionally watch enabled namespaces, and enroll already-started-but-newly-enrolled pods in a similar fashion.

## Privileges required

```mermaid
graph LR
    subgraph Client Node
        Client
        CZ["Ztunnel"]
    end
    subgraph Server Node
        Server
        SZ["Ztunnel"]
    end
    Client--Plain-->CZ
    CZ-."HBONE (target)".->Server
    CZ--"HBONE (actual)"-->SZ
    SZ--Plain-->Server
```

### Pooling

User connections can be multiplexed over shared HBONE connections.

	"istio.io/istio/pkg/slices"
	"istio.io/istio/pkg/util/sets"
	dep "istio.io/istio/tools/istio-iptables/pkg/dependencies"
)

var log = istiolog.RegisterScope("ambient", "ambient controller")

// Adapts CNI to ztunnel server. decoupled from k8s for easier integration testing.
type NetServer struct {
	ztunnelServer        ZtunnelServer
	currentPodSnapshot   *podNetnsCache
	iptablesConfigurator *iptables.IptablesConfigurator

AGENT_BINARIES:=./pilot/cmd/pilot-agent
STANDARD_BINARIES:=./istioctl/cmd/istioctl \
  ./pilot/cmd/pilot-discovery \
  ./pkg/test/echo/cmd/client \
  ./pkg/test/echo/cmd/server \
  ./samples/extauthz/cmd/extauthz \
  ./operator/cmd/operator

# These are binaries that require Linux to build, and should
# be skipped on other platforms. Notably this includes the current Linux-only Istio CNI plugin

	fs := &fakeServer{testWG: wg}

	fs.On("AddPodToMesh",
		ctx,
		pod,
		util.GetPodIPsIfPresent(pod),
		"",
	).Return(nil)

	server := &meshDataplane{
		kubeClient: client.Kube(),
		netServer:  fs,
	}

	handlers := setupHandlers(ctx, client, server, "istio-system")
	client.RunAndWait(ctx.Done())
	go handlers.Start()

	// label the namespace

}

func (mrdir *mockInterceptRuleMgr) Program(podName, netns string, redirect *Redirect) error {
	mrdir.lastRedirect = append(mrdir.lastRedirect, redirect)
	return nil
}

// returns the test server URL and a dispose func for the test server
func setupCNIEventClientWithMockServer(serverErr bool) (string, func() bool) {
	cniAddServerCalled := false
	// replace the global CNI client with mock

// K8sArgs is the valid CNI_ARGS used for Kubernetes
// The field names need to match exact keys in containerd args for unmarshalling
// https://github.com/containerd/containerd/blob/ced9b18c231a28990617bc0a4b8ce2e81ee2ffa1/pkg/cri/server/sandbox_run.go#L526-L532
type K8sArgs struct {
	types.CommonArgs
	K8S_POD_NAME               types.UnmarshallableString // nolint: revive, stylecheck

		// Start UDS log server
		udsLogger := udsLog.NewUDSLogger()
		if err = udsLogger.StartUDSLogServer(cfg.InstallConfig.LogUDSAddress, ctx.Done()); err != nil {
			log.Errorf("Failed to start up UDS Log Server: %v", err)
			return
		}

		// Creates a basic health endpoint server that reports health status
		// based on atomic flag, as set by installer
		// TODO nodeagent watch server should affect this too, and drop atomic flag