# Istio CNI Node Agent

The Istio CNI Node Agent is responsible for several things

- Install an Istio CNI plugin binary on each node's filesystem, updating that node's CNI config in e.g (`/etc/cni/net.d`), and watching the config and binary paths to reinstall if things are modified.

// will be redeployed.
func (in *Installer) Run(ctx context.Context) error {
	installedBins, err := in.installAll(ctx)
	if err != nil {
		return err
	}
	installLog.Info("Installation succeed, start watching for re-installation.")

	for {
		// if sleepWatchInstall yields without error, that means the config might have been modified in some fashion.

func startInstallServer(ctx context.Context, serverConfig *config.Config, t *testing.T) {
	readyFlag := &atomic.Value{}
	installer := install.NewInstaller(&serverConfig.InstallConfig, readyFlag)

	t.Logf("CNI installer created, watching...")
	// installer.Run() will block indefinitely, and attempt to permanently "keep"
	// the CNI binary installed.
	if err := installer.Run(ctx); err != nil {

			args: strings.Split("service productpage", " "),
			expectedOutput: `Service: productpage
DestinationRule: productpage for "productpage"
   WARNING POD DOES NOT MATCH ANY SUBSETS.  (Non matching subsets v1)
   Matching subsets: 
      (Non-matching subsets v1)
   No Traffic Policy
VirtualService: bookinfo
   Route to host "productpage" with weight 30%
   Route to host "productpage2" with weight 20%

                "matcher_tree": {
                  "input": {
                    "name": "ip",
                    "typed_config": {
                      "@type": "type.googleapis.com/envoy.extensions.matching.common_inputs.network.v3.DestinationIPInput"
                    }
                  },
                  "custom_match": {
                    "name": "ip",
                    "typed_config": {

pilot:
  env:
    # 1.21 behavioral changes
    ENABLE_EXTERNAL_NAME_ALIAS: "false"
    PERSIST_OLDEST_FIRST_HEURISTIC_FOR_VIRTUAL_SERVICE_HOST_MATCHING: "true"
    VERIFY_CERTIFICATE_AT_CLIENT: "false"
    ENABLE_AUTO_SNI: "false"

    # 1.22 behavioral changes
    ENABLE_RESOLUTION_NONE_TARGET_PORT: "false"

meshConfig:
  # 1.22 behavioral changes

pilot:
  env:
    # 1.21 behavioral changes
    ENABLE_EXTERNAL_NAME_ALIAS: "false"
    PERSIST_OLDEST_FIRST_HEURISTIC_FOR_VIRTUAL_SERVICE_HOST_MATCHING: "true"
    VERIFY_CERTIFICATE_AT_CLIENT: "false"
    ENABLE_AUTO_SNI: "false"

    # 1.22 behavioral changes
    ENABLE_RESOLUTION_NONE_TARGET_PORT: "false"

meshConfig:
  # 1.22 behavioral changes

pilot:
  env:
    # 1.21 behavioral changes
    ENABLE_EXTERNAL_NAME_ALIAS: "false"
    PERSIST_OLDEST_FIRST_HEURISTIC_FOR_VIRTUAL_SERVICE_HOST_MATCHING: "true"
    VERIFY_CERTIFICATE_AT_CLIENT: "false"
    ENABLE_AUTO_SNI: "false"

    # 1.22 behavioral changes
    ENABLE_RESOLUTION_NONE_TARGET_PORT: "false"

meshConfig:
  # 1.22 behavioral changes

  // an API request to apps/v1beta1 deployments would be converted and sent to the webhook
  // with `kind: {group:"apps", version:"v1", kind:"Deployment"}` (matching the rule the webhook registered for),
  // and `requestKind: {group:"apps", version:"v1beta1", kind:"Deployment"}` (indicating the kind of the original API request).
  //

                "matcher_tree": {
                  "input": {
                    "name": "ip",
                    "typed_config": {
                      "@type": "type.googleapis.com/envoy.extensions.matching.common_inputs.network.v3.DestinationIPInput"
                    }
                  },
                  "custom_match": {
                    "name": "ip",
                    "typed_config": {