This repository showcases the terraform template that will help you to create EKS cluster on AWS.

Note - Above architecture doesn't reflect all the components that are created by this template. However, it does give an idea about core infrastructure that will be created.

• Creates a new VPC with CIDR Block - 10.15.0.0/19 (i.e. 8190 IPs in a VPC) in a region of your choice. Feel free to change it, values are variables.tf.
• Creates 3 public & 3 private subnets with each size of 1024 IP addresses in each zones
• Creates security groups required for cluster and worker nodes.
• Creates recommended IAM service and EC2 roles required for EKS cluster.
• Creates Internet & NAT Gateway required for public and private communications.
• Routing Table and routes for public and private subnets.

Before you execute this template make sure following dependencies are met.

• Install terraform
• Configure AWS CLI - make sure you configure AWS CLI with admin privileges
• AWS iam authenticator - Amazon EKS uses IAM to provide authentication to your Kubernetes cluster through the AWS IAM Authenticator for Kubernetes.
• Make sure a valid SSH key pair exists under the ~/.ssh/ directory. If it does not exist, create a new SSH Key Pair for authentication by using the command ssh-keygen -t rsa

$ git clone https://github.com/MediaIQ/terraform-aws-eks-cluster.git
$ cd terraform-aws-eks-cluster

$ terraform init

The terraform plan command is used to create an execution plan. Always a good practice to run it before you apply it to see what all resources will be created.

This will ask you to specify cluster name and worker node instance type.

$ terraform plan

var.cluster-name
  Enter eks cluster name - example like eks-demo, eks-dev etc

  Enter a value: eks-demo

var.region
  Enter region you want to create EKS cluster in

  Enter a value: us-east-1

var.ssh_key_pair
  Enter SSH keypair name that already exist in the account

  Enter a value: eks-keypair

var.worker-node-instance_type
  enter worker node instance type

  Enter a value: t2.medium

$ terraform apply

$ aws eks --region <AWS-REGION> update-kubeconfig --name <CLUSTER-NAME>

Note:- If AWS CLI and AWS iam authenticator setup correctly, above command should set up kubeconfig file in ~/.kube/config in your system.

$ kubectl get svc

Output:

NAME             TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
svc/kubernetes   ClusterIP   10.100.0.1   <none>        443/TCP   1m

Once cluster is verified successfully, it's time to create a configMap to add the worker nodes into the cluster. We have configured output with this template which will produce the configMap file content that you paste in aws-auth.yaml.

$ kubectl apply -f aws-auth.yaml

$ kubectl get no -w

Note:- You should be seeing nodes joining the cluster within less than minutes.

Create a new eks-worker-node-v1.tf file with different name and below changes you have to do for EKS cluster upgrade.

• Change the userdata name to new version(eks-worker-node-upgrade-v2.tf) and should not conflict with old one.
• Change the Launch configuration and autoscaling group name to new version and should not conflict with old one.
• Change the ami to which your going upgrade EKS version provided by AWS -- ##eks-worker-ami -- change to new version
• In the new worker node file(eks-worker-node-upgrade-v2.tf), we have updated extra arguments for dedicated node(taint).
• Once you apply new .tf file and the new nodes will spin up , post that move workloads to the new one and delete old nodes.
• Please refer eks-worker-node-upgrade-v2.tf file to upgrade the EKS cluster for reference and below steps to upgrade the worker nodes.

$ terraform apply  

$ kubectl get no
  NAME                       STATUS   ROLES   AGE   VERSION
  ip-10-0-87-98.ec2.inetenal  Ready   <none>  21d   v1.12.7
  ip-10-0-15-24.ec2.inetenal  Ready   <none>  21d   v1.12.7
  ip-10-0-23-100.ec2.inetenal  Ready   <none>  21d   v1.13.7-eks-c57ff8
  ip-10-0-14-23.ec2.inetenal  Ready   <none>  21d   v1.13.7-eks-c57ff8

$ kubectl cordon nodename (old nodes)

$ kubectl drain nodename (old nodes)

We are happy to accept the changes that you think can help the utilities grow.

Here are some things to note:

• Raise a ticket for any requirement
• Discuss the implementation requirement or bug fix with the team members
• Fork the repository and solve the issue in one single commit
• Raise a PR regarding the same issue and attach the required documentation or provide a more detailed overview of the changes