RegistryCache

The registrycaches.core.kyma-project.io CustomResourceDefinition (CRD) is a detailed description of the kind of data and the format used to track the installation state of the Registry Cache module on a Kyma runtime cluster. To get the up-to-date CRD and show the output in the yaml format, run this command:

kubectl get crd registrycaches.core.kyma-project.io -o yaml

Overview

Kyma Lifecycle Manager (KLM) creates this resource automatically when you install the Registry Cache module on a Kyma runtime cluster. You do not create or delete this resource directly — the module lifecycle infrastructure manages it.

The RegistryCache custom resource (CR) tracks whether the Registry Cache admission webhook is healthy and the module is fully operational. The controller reconciles this resource and transitions it through a set of well-defined states.

Sample Custom Resource

This is a sample RegistryCache resource in the Ready state:

apiVersion: core.kyma-project.io/v1beta1
kind: RegistryCache
metadata:
  name: registry-cache
  namespace: kyma-system
  finalizers:
    - registry-cache.kyma-project.io/finalizer
status:
  state: Ready
  conditions:
    - type: Starting
      status: "True"
      reason: Ready
      message: Starting module
      observedGeneration: 1

Custom Resource Parameters

This table lists all the parameters of a RegistryCache resource together with their descriptions:

Parameter	Required	Description
metadata.name	Yes	Specifies the name of the CR.
metadata.namespace	Yes	The namespace in which the CR is created.
spec	No	Empty — the RegistryCache CR has no configurable spec fields. All configuration is done through RegistryCacheConfig resources.

Status Fields

Field	Description
status.state	The current state of the Registry Cache module. See State Lifecycle.
status.conditions	A list of Kubernetes standard conditions. The condition type Starting reports the health of the admission webhook server.

State Lifecycle

The controller transitions the RegistryCache CR through the following states:

State	Description
(empty)	Initial state — the resource has just been created and has not yet been processed.
Processing	The controller is checking whether the admission webhook is ready.
Ready	The admission webhook is healthy and the module is fully operational.
Error	The admission webhook is unhealthy. The controller re-checks at the health interval (every 30 seconds).
Deleting	A deletion timestamp was set on the resource; the controller is removing the finalizer.

The normal lifecycle is: (empty) → Processing → Ready.

If the webhook becomes unhealthy while in Ready, the state transitions to Error. The controller retries every 30 seconds and returns to Ready once the webhook is healthy again.

Related Resources and Components

These are the resources related to this CR:

Custom resource	Description
RegistryCacheConfig	The user-facing resource for configuring a caching layer for a specific upstream registry. See Registry Cache Module.

These components use this CR:

Component	Description
Registry Cache controller	Reconciles RegistryCache CRs and drives status transitions.
Kyma Lifecycle Manager (KLM)	KCP component that creates and deletes the RegistryCache CR as part of module installation and removal.