Creating an AWS EKS cluster

The creation of an AWS EKS cluster is complex, and requires adding many AWS EC2 resources. The Anjuna Nitro Kubernetes tools provide a terraform script that makes it very easy to create a Nitro-capable AWS EKS cluster. The script is based on the terraform eks module (see https://registry.terraform.io/modules/terraform-aws-modules/eks/aws/latest for a complete reference in this module).

Configure the cluster

First we create a file named terraform.tfvars. This file will contain the configurable variables specific to your cluster. The values in this file consist of optional values that override defaults in variables.tf and mandatory values for variables defined in variables.tf that do not have a defined default.

You can create a starter terraform.tfvars file with the following command:

$ cd terraform
$ ./gen-variables.sh

Now edit terraform.tfvars to customize your cluster. Commented out values show the default value that is used when they are not defined. If you are unsure what a variable controls, see the description in variables.tf.

The default value for cluster_version is "1.21", which is the latest version Anjuna supports. If you wish to use an earlier version, make sure that you also install the kubectl version that matches your cluster_version.

Create the cluster

Before running other terraform commands, you must initialize the directory with this one-off command. All remaining commands assume that you are in the terraform subdirectory.

$ terraform init

Next you will create the AWS infrastructure. If you wish to see and approve the AWS assets before they are created, skip the optional -auto-approve flag.

$ terraform apply -auto-approve

Creating an AWS EKS cluster is a complex operation and will take some time to complete.

The Terraform scripts will create EC2 instances that are accessible as a public instance. This makes it easy to connect to the EC2 host for debugging purposes and should be used only for testing purposes.

A real AWS EKS cluster would not configure those EC2 instances in such a way. Please inspect the Terraform scripts and update them to create and deploy a cluster that is consistent with the best security practices for deploying AWS EKS cluster.

Congratulations, you should have a running EC2 cluster with a single Nitro-capable node. To update the cluster and add/remove nodes, just update the file terraform.tfvars with the proper parameters (for example, update the worker_node_count value).

The final step is to configure kubectl to have the ability to manage your AWS EKS cluster:

$ aws eks --region "$(terraform output -raw region)" update-kubeconfig --name "$(terraform output -raw cluster_name)"

If the cluster is properly created and kubectl configured correctly, the following command should show a single node in your cluster:

$ kubectl get nodes