Glen Knight

Amazon EKS Windows Container Support now Generally Available

October 8, 2019 by knightglen_sruobz

In March of this year, we announced a preview of Windows Container support on Amazon Elastic Kubernetes Service and invited customers to experiment and provide us with feedback. Today, after months of refining the product based on that feedback, I am delighted to announce that  Windows Container support is now generally available.

Many development teams build and support applications designed to run on Windows Servers and with this announcement they can now deploy them on Kubernetes alongside Linux applications. This ability will provide more consistency in system logging, performance monitoring, and code deployment pipelines.

Amazon Elastic Kubernetes Service simplifies the process of building, securing, operating, and maintaining Kubernetes clusters, and allows organizations to focus on building applications instead of operating Kubernetes. We are proud to be the first Cloud provider to have General Availability of Windows Containers on Kubernetes and look forward to customers unlocking the business benefits of Kubernetes for both their Windows and Linux workloads.

To show you how this feature works, I will need an Amazon Elastic Kubernetes Service cluster. I am going to create a new one, but this will work with any cluster that is using Kubernetes version 1.14 and above. Once the cluster has been configured, I will add some new Windows nodes and deploy a Windows application. Finally, I will test the application to ensure it is running as expected.

The simplest way to get a cluster set up is to use eksctl, the official CLI tool for EKS. The command below creates a cluster called demo-windows-cluster and adds two Linux nodes to the cluster. Currently, at least one Linux node is required to support Windows node and pod networking, however, I have selected two for high availability and we would recomend that you do the same.

eksctl create cluster 
--name demo-windows-cluster 
--version 1.14 
--nodegroup-name standard-workers 
--node-type t3.medium 
--nodes 2 
--nodes-min 1 
--nodes-max 3 
--node-ami auto

Starting with eksctl version 0.7, a new utility has been added called install-vpc-controllers. This utility installs the required VPC Resource Controller and VPC Admission Webhook into the cluster. These components run on Linux nodes and are responsible for enabling networking for incoming pods on Windows nodes. To use the tool we run the following command.

eksctl utils install-vpc-controllers --name demo-windows-cluster --approve

If you don’t want to use eksctl we also provide guides in the documentation on how you can run PowerShell or Bash scripts, to achieve the same outcome.

Next, I will need to add some Windows Nodes to our cluster. If you use eksctl to create the cluster then the command below will work. If you are working with an existing cluster, check out the documentation for instructions on how to create a Windows node group and connect it to your cluster.

eksctl create nodegroup 
--region us-west-2 
--cluster demo-windows-cluster 
--version 1.14 
--name windows-ng 
--node-type t3.medium 
--nodes 3 
--nodes-min 1 
--nodes-max 4 
--node-ami-family WindowsServer2019FullContainer 
--node-ami ami-0f85de0441a8dcf46

The most up to date Windows AMI ID for your region can be found by querying the AWS SSM Parameter Store. Instructions to do this can be found in the Amazon EKS documentation.

Now I have the nodes up and running I can deploy a sample application. I am using a YAML file from the AWS containers roadmap GitHub repository. This file configures an app that consists of a single container that runs IIS which in turn hosts a basic HTML page.

kubectl apply -f https://raw.githubusercontent.com/aws/containers-roadmap/master/preview-programs/eks-windows-preview/windows-server-IIS.yaml

These are Windows containers, which are often a little larger than Linux containers and therefore take a little longer to download and start-up. I monitored the progress of the deployment by running the following command.

kubectl get pods -o wide --watch

I waited for around 5 minutes for the pod to transition to the Running state. I then executed the following command, which connects to the pod and initializes a PowerShell session inside the container. The windows-server-iis-66bf9745b-xsbsx property is the name of the pod, if you are following along with this your name will be different.

kubectl exec -it windows-server-iis-66bf9745b-xsbsx powershell

Once you are conected to the PowerShell session you can now execute PowerShell as if you were using the terminal inside the container. Therefore if we run the command below we should get some information back about the news blog

Invoke-WebRequest -Uri https://aws.amazon.com/blogs/aws/ -UseBasicParsing

To exit the PowerShell session I type exit and it returns me to my terminal. From there I can inspect the service that was deployed by the sample application, I type the following command:

kubectl get svc windows-server-iis-service

This gives me the following output that describes the service:

NAME				TYPE 		CLUSTER-IP 	EXTERNAL-IP 				PORT(S) 	AGE
windows-server-iis-service 	LoadBalancer 	xx.xx.xxx.xxx 	unique.us-west-2.elb.amazonaws.com 	80:32750/TCP 	54s

The External IP should be the address of a load balancer. If I type this URL into a browser and append /default.html then it will load a HTML page that was created by the sample application deployment. This is being served by our IIS server from one of the Windows containers I deployed.

So there we have it, Windows Containers running on Amazon Elastic Kubernetes Service. For more details, please check out the documentation. Amazon EKS Windows Container Support is available in all the same regions as Amazon EKS is available, and pricing details can be found over here.

We have a long roadmap for Amazon Elastic Kubernetes Service, but we are eager to get your feedback and will use it to drive our prioritization process. Please take a look at this new feature and let us know what you think!

Source: AWS News