oc get image.config.openshift.io/cluster -o yaml

apiVersion: config.openshift.io/v1
kind: Image
metadata:
  annotations:
    include.release.openshift.io/ibm-cloud-managed: "true"
    include.release.openshift.io/self-managed-high-availability: "true"
    include.release.openshift.io/single-node-developer: "true"
    release.openshift.io/create-only: "true"
  creationTimestamp: "..."
  generation: 3
  name: cluster
  ownerReferences:
  - apiVersion: config.openshift.io/v1
    kind: ClusterVersion
    name: version
    uid: ...
  resourceVersion: "..."
  uid: ...
spec:
  registrySources:
    insecureRegistries:
    - harbor.mydomain.tld
    - harbor.otherdomain.tld

Mêttre à jour et appliquer !