catch pod creation events and notify the CNI agent early enough to set up network redirection before the pod is fully started. This is necessary because the CNI plugin is effectively the first thing to see a scheduled pod - before the K8S control plane will see things like the pod IP or networking info, the CNI will - but the CNI plugin alone is not sufficient to handle all pod events (already-started pod updates, rebuilding current state on CNI restart) that the node agent cares about.

##...

	overrideHelpStr = `If true, allow revision tags to be overwritten, otherwise reject revision tag updates that
overwrite existing revision tags.`
	revisionHelpStr = "Control plane revision to reference from a given revision tag"
	tagCreatedStr   = `Revision tag %q created, referencing control plane revision %q. To enable injection using this
revision tag, use 'kubectl label namespace <NAMESPACE> istio.io/rev=%s'
`

    #
    # certSigners:
    #   - clusterissuers.cert-manager.io/istio-ca
    certSigners: []
    # enable pod disruption budget for the control plane, which is used to
    # ensure Istio control plane components are gradually upgraded or recovered.
    defaultPodDisruptionBudget:
      enabled: true
      # The values aren't mutable due to a current PodDisruptionBudget limitation

three main components:

- [MeshConfig](https://github.com/istio/api/blob/master/mesh/v1alpha1/config.proto) for runtime config consumed directly by Istio
control plane components.
- [Component configuration API](https://github.com/istio/api/blob/00671adacbea20f941cb20cce021bc63cbad1840/operator/v1alpha1/operator.proto#L42-L93), for managing

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net"
	"net/url"
	"os"
	"strings"

	discovery "github.com/envoyproxy/go-control-plane/envoy/service/discovery/v3"
	xdsstatus "github.com/envoyproxy/go-control-plane/envoy/service/status/v3"
	"google.golang.org/grpc"
	v1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	"istio.io/api/label"

		var icpTag string
		// create normalized tags for multiple control plane revisions
		for _, icp := range *icps {
			if icp.Revision != revision {
				continue
			}
			tagVer, err := GetTagVersion(icp.Info.GitTag)
			if err != nil {
				return err
			}
			icpTags = append(icpTags, tagVer)
		}
		// sort different versions of control plane revisions
		sort.Strings(icpTags)

    return 9
  fi
  # Workaround kind issue causing taints to not be removed in 1.24
  kubectl taint nodes "${NAME}"-control-plane node-role.kubernetes.io/control-plane- 2>/dev/null || true

  # Determine what CNI to install
  case "${KUBERNETES_CNI:-}" in 

    "calico")
      echo "Installing Calico CNI"
      install_calico "" "$(dirname "$CONFIG")"

	matcher "github.com/cncf/xds/go/xds/type/matcher/v3"
	listener "github.com/envoyproxy/go-control-plane/envoy/config/listener/v3"
	route "github.com/envoyproxy/go-control-plane/envoy/config/route/v3"
	hcm "github.com/envoyproxy/go-control-plane/envoy/extensions/filters/network/http_connection_manager/v3"
	tcp "github.com/envoyproxy/go-control-plane/envoy/extensions/filters/network/tcp_proxy/v3"
	"sigs.k8s.io/yaml"

            "axisCenteredZero": false,
            "axisColorMode": "text",
            "axisLabel": "",
            "axisPlacement": "auto",
            "barAlignment": 0,
            "drawStyle": "line",
            "fillOpacity": 10,
            "gradientMode": "none",
            "hideFrom": {
              "legend": false,
              "tooltip": false,
              "viz": false
            },

* Be lightweight enough to not limit adoption.
  * This puts a much tighter budget on CPU, memory, latency, and throughput requirements than traditional Istio sidecars.

Ztunnel was not designed to be a feature-rich data plane.
Quite the opposite - an *aggressively* small feature set is the key feature that makes ztunnel viable.