### Install Istio CRDs

This is the first step of the installation. Please do not remove or edit any CRD - config currently requires
all CRDs to be present. On each upgrade it is recommended to reapply the file, to make sure
you get all CRDs.  CRDs are separated by release and by component type in the CRD directory.

Istio has strong integration with certmanager.  Some operators may want to keep their current certmanager

### Controllers overview

Below provides a high level overview of controllers in Istiod. For more information about each controller, consulting the controllers Go docs is recommended.

```mermaid
graph BT
    crd("CRD Watcher")
    subgraph Service Discovery
        ksd("Kubernetes Controller")
        sesd("Service Entry Controller")
        msd("Memory Controller")
        asd("Aggregate")
        ksd--Join-->asd

	sed -e '1 i {{- if .Values.global.configCluster }}' -e '$$ a {{- end }}' manifests/charts/base/crds/crd-all.gen.yaml > manifests/charts/istiod-remote/templates/crd-all.gen.yaml
	sed -e '1 i {{- if .Values.global.configCluster }}' -e '$$ a {{- end }}' manifests/charts/base/templates/default.yaml > manifests/charts/istiod-remote/templates/default.yaml