Box 1: Azure Container Registry -
Azure services like Azure Container Registry (ACR) and Azure Container Instances (ACI) can be used and connected from independent container orchestrators like kubernetes (k8s). You can set up a custom ACR and connect it to an existing k8s cluster to ensure images will be pulled from the private container registry instead of the public docker hub.
Box 2: An Azure service principal
When you're using Azure Container Registry (ACR) with Azure Kubernetes Service (AKS), an authentication mechanism needs to be established. You can set up
AKS and ACR integration during the initial creation of your AKS cluster. To allow an AKS cluster to interact with ACR, an Azure Active Directory service principal is used.
Reference:
https://thorsten-hans.com/how-to-use-private-azure-container-registry-with-kubernetes
https://docs.microsoft.com/en-us/azure/aks/cluster-container-registry-integration
