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MakendranG for Kubernetes Community Days Chennai

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What is HostProcess containers in AKS?.

HostProcess / Privileged containers lengthen the Windows container model to allow a wider vary of Kubernetes cluster administration scenarios. HostProcess containers run at once on the host and preserve behavior and access similar to that of a ordinary process.

HostProcess containers allow users to package and distribute management operations and functionalities that require host access whilst protecting versioning and deployment strategies provided by means of containers.

A privileged DaemonSet can elevate out adjustments or reveal a Linux host on Kubernetes however not Windows hosts. HostProcess containers are the Windows equal of host elevation.


  • HostProcess containers require Kubernetes 1.23 or greater.
  • HostProcess containers require containerd 1.6 or higher container runtime.
  • HostProcess pods can only include HostProcess containers. This is a current predicament of the Windows operating system. Non-privileged Windows containers cannot share a vNIC with the host IP namespace.
  • HostProcess containers run as a system on the host. The solely isolation these containers have from the host is the resource constraints imposed on the HostProcess person account.
  • Filesystem isolation and Hyper-V isolation are not supported for HostProcess containers.
  • Volume mounts are supported and are set up under the container volume. See Volume Mounts.
  • A confined set of host consumer accounts are accessible for Host Process containers through default. See Choosing a User Account.
  • Resource limits such as disk, memory, and cpu count, work the same way as trend as processes on the host.
  • Named pipe mounts and Unix domain sockets are now not without delay supported, but can be accessed on their host path, for instance \.\pipe*.

Run a HostProcess workload

To use HostProcess features with your deployment, set privileged: true, hostProcess: true, and hostNetwork: true:

            privileged: true
              hostProcess: true
      hostNetwork: true

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To run an example workload that uses HostProcess features on an existing AKS cluster, create kcdhostprocess.yaml.

The example workload can be run using kubectl.

kubectl apply -f kcdhostprocess.yaml
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You should see the following output:

$ kubectl apply -f kcdhostprocess.yaml
daemonset.apps/privileged-daemonset created
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The features of HostProcess can be verified by viewing the logs.

The name of the Pod can be found in the kube-systemnamespace.

$ kubectl get pods --namespace kube-system

NAME                                  READY   STATUS    RESTARTS   AGE
privileged-daemonset-12345            1/1     Running   0          2m13s
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You can use the log to view the logs and verify the administrator rights.

$ kubectl logs privileged-daemonset-12345 --namespace kube-system
InvalidOperation: Unable to find type [Security.Principal.WindowsPrincipal].
Process has admin rights:
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