# (Select a specific control plane in an in-cluster canary Istio configuration.)
  istioctl x internal-debug syncz --xds-label istio.io/rev=default
`,
		RunE: func(c *cobra.Command, args []string) error {
			kubeClient, err := ctx.CLIClientWithRevision(opts.Revision)
			if err != nil {
				return err
			}
			if len(args) == 0 {

  # (Certificates must be obtained before this step.  The --cert-dir flag lets istioctl bypass the Kubernetes API server.)
  istioctl ps --xds-address istio.example.com:15012 --cert-dir ~/.istio-certs

  # Retrieve proxy status information via XDS from specific control plane in multi-control plane in-cluster configuration

```

3) `istio-control/istio-discovery` chart installs a revision of istiod.

```console
 helm install -n istio-system istiod manifests/charts/istio-control/istio-discovery --set profile=openshift
```

4) `gateways` charts install a load balancer with `ingress` and `egress`.

Ingress secrets and access should be separated from the control plane.

```console

metadata:
  {{- if .Values.pilot.enabled }}
  # when local istiod is enabled, we can't use istiod service name to reach the remote control plane
  name: istiod{{- if .Values.revision }}-{{ .Values.revision}}{{- end }}-remote
  {{- else }}
  # when local istiod isn't enabled, we can use istiod service name to reach the remote control plane
  name: istiod{{- if .Values.revision }}-{{ .Values.revision}}{{- end }}
  {{- end }}
  namespace: {{ .Release.Namespace }}

	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'
`

### Install Control plane

This can run in any cluster. A mesh should have at least one cluster should run Pilot or equivalent XDS server,
and it is recommended to have Pilot running in each region and in multiple availability zones for multi cluster.

```bash
iop istio-control istio-discovery $IBASE/istio-control/istio-discovery \
            --set global.istioNamespace=istio-system

	cp manifests/charts/istio-control/istio-discovery/files/injection-template.yaml manifests/charts/istiod-remote/files
	cp manifests/charts/istio-control/istio-discovery/files/gateway-injection-template.yaml manifests/charts/istiod-remote/files
	cp manifests/charts/istio-control/istio-discovery/templates/istiod-injector-configmap.yaml manifests/charts/istiod-remote/templates

      # stackdriver filter settings.
      stackdriver:
        enabled: false
  # Revision is set as 'version' label and part of the resource names when installing multiple control planes.
  revision: ""

  # Revision tags are aliases to Istio control plane revisions
  revisionTags: []

  # For Helm compatibility.
  ownerName: ""

package multixds

// multixds knows how to target either central Istiod or all the Istiod pods on a cluster.

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"

kube-system        coredns-5dd5756b68-mgjn9                             10.244.0.2  ambient-control-plane None                                TCP
kube-system        coredns-5dd5756b68-nzlpw                             10.244.0.3  ambient-control-plane None                                TCP
local-path-storage local-path-provisioner-6f8956fb48-vvnpn              10.244.0.4  ambient-control-plane None                                TCP