Merge pull request #211195 from tomvcassidy/windowsServerMigrationGuide

FAQ Additions for Migration Guidance

Author: prmerger-automator[bot]

articles/container-instances/container-instances-faq.yml

@@ -38,6 +38,9 @@ sections:
       - question: |
           Windows Server 2016 base images
         answer: |
+          > [!IMPORTANT]
+          > From now through 31 December 2022, you can continue to deploy Windows Server 2016 container groups on Azure Container Instances. After this date, Windows Server 2016 images will no longer be supported. See [How do I migrate my Windows Server 2016 container groups to Windows Server 2019 images?](#how-do-i-migrate-my-windows-server-2016-container-groups-to-windows-server-2019-images-) for instructions on how to transition your workloads.
+
           * [Nano Server](https://hub.docker.com/_/microsoft-windows-nanoserver): `sac2016`, `10.0.14393.3568` or newer
           * [Windows Server Core](https://hub.docker.com/_/microsoft-windows-servercore): `ltsc2016`,  `10.0.14393.3568` or newer
           
@@ -64,6 +67,34 @@ sections:
         answer: |
           ACI supports image pulls from ACR and other third-party container registries such as DockerHub. ACI supports image pulls from ACR and other third-party OCI compatible container registries such as DockerHub with an endpoint that is publicly exposed to the internet.
 
+      - question: |
+          How do I migrate my Windows Server 2016 container groups to Windows Server 2019 images?
+        answer: |
+          1. Identify what Windows base image you are currently using.
+
+              If you're pulling directly from Microsoft Container Registry (MCR), then that image name is your base image.
+
+              If you're working with a private registry, you'll need to look at your Dockerfile to identify the base image, which will be stated after the ['FROM' line](https://docs.docker.com/engine/reference/builder/#from).
+
+          2. Select the new base image you want to use from Windows Server 2019. Below are some examples of commonly used Windows Server 2016 images on Azure Container Instances and our recommendations for replacement Windows Server 2019 images.
+
+              | Windows Server 2016 Image | Recommended Windows Server 2019 Images |
+              | - | - |
+              | mcr.microsoft.com/windows/servercore/iis | mcr.microsoft.com/windows/servercore/iis:windowsservercore-ltsc2019 |
+              | mcr.microsoft.com/windows/servercore:ltsc2016 | mcr.microsoft.com/windows/servercore:ltsc2019 |
+
+              Read about [image discovery](https://docs.microsoft.com/virtualization/windowscontainers/manage-containers/container-base-images#image-discovery) to learn more.
+
+              > [!NOTE]
+              > If you would like assistance selecting your new base image, please create an Azure Support Ticket.
+
+          3. Follow the [Update containers in Azure Container Instances how-to guide](container-instances-update.md) to update your ACI container group to use your new base image.
+
+              If you're using MCR for your container registry, you can pass the MCR image name directly into the [container group image parameter](https://docs.microsoft.com/en-us/azure/templates/microsoft.containerinstance/containergroups?tabs=bicep&pivots=deployment-language-bicep#containerproperties).
+
+              If you're using a private container registry, please follow the steps in [Upgrade containers to a new version of the Windows operating system](https://docs.microsoft.com/en-us/virtualization/windowscontainers/deploy-containers/upgrade-windows-containers#create-new-container-instances-using-the-new-os-version). Make sure the container group's [image registry parameters](https://docs.microsoft.com/en-us/azure/templates/microsoft.containerinstance/containergroups?tabs=bicep&pivots=deployment-language-bicep#imageregistrycredential) are updated if you have changed them.
+          
+
   - name: Availability and quotas
     questions:
       - question: |