<p>through my testing some new features for AKS clusters i want to enable managed identities feature for my azure k8s cluster, can anyone just simply tell me what the main benefit to use this ? and do i need in this way an externel DNS zone ?</p>

jorg-m
<blockquote>
  <p>Currently, an Azure Kubernetes Service (AKS) cluster (specifically,
  the Kubernetes cloud provider) requires a service principal to create
  additional resources like load balancers and managed disks in Azure.
  Either you must provide a service principal or AKS creates one on your
  behalf. Service principals typically have an expiration date. Clusters
  eventually reach a state in which the service principal must be
  renewed to keep the cluster working. Managing service principals adds
  complexity.</p>
  
  <p>Managed identities are essentially a wrapper around service
  principals, and make their management simpler. To learn more, read
  about managed identities for Azure resources.</p>
  
  <p>AKS creates two managed identities:</p>
  
  <p>System-assigned managed identity: The identity that the Kubernetes
  cloud provider uses to create Azure resources on behalf of the user.
  The life cycle of the system-assigned identity is tied to that of the
  cluster. The identity is deleted when the cluster is deleted.
  User-assigned managed identity: The identity that's used for
  authorization in the cluster. For example, the user-assigned identity
  is used to authorize AKS to use Azure Container Registries (ACRs), or
  to authorize the kubelet to get metadata from Azure. Add-ons also
  authenticate using a managed identity. For each add-on, a managed
  identity is created by AKS and lasts for the life of the add-on. For
  creating and using your own VNet, static IP address, or attached Azure
  disk where the resources are outside of the MC_* resource group, use
  the PrincipalID of the cluster to perform a role assignment. For more
  information on role assignment, see Delegate access to other Azure
  resources.</p>
</blockquote>

<p>in short - to ease management</p>
