Create Kubernetes Cluster on AWS EKS

 

In this post we will review the steps to create a kubernetes cluster on AWS EKS service.

First we need to configure AWS CLI credentails and zone. I like to use a script to handle these configurations:

env.sh

export AWS_SHARED_CREDENTIALS_FILE=${PWD}/credentials
export AWS_CONFIG_FILE=${PWD}/config
export AWS_PAGER=""

Where the credentials file contains your AWS access key, and the config file contains the region configuration.

credentials

[default]
aws_access_key_id = XXXXXXXXXXXXXXXXXXXX
aws_secret_access_key = XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

config

[default]
region=us-east-1
output=json

AWS EKS cluster is partly managed by the eksctl CLI, which creates several AWS cloud formation templates that configure the kubernetes cluster entities on AWS.

To install eksctl, use the following:

curl --silent --location "https://github.com/weaveworks/eksctl/releases/latest/download/eksctl_$(uname -s)_amd64.tar.gz" | tar xz -C /tmp
sudo mv /tmp/eksctl /usr/local/bin

Next create a YAML file to configure the cluster:

cluster.yaml

apiVersion: eksctl.io/v1alpha5
kind: ClusterConfig

metadata:
  name: my-eks-cluster
  region: us-east-1

availabilityZones:
  - us-east-1a
  - us-east-1b

nodeGroups:
  - name: ng-1
    instanceType: m5.large
    desiredCapacity: 2
    ssh:
      publicKeyPath: ./id_rsa.pub
    availabilityZones:
      - us-east-1a

Notice that the file points to an existing SSH public key, which will be used for the EC2 instances that are part of the cluster.

Also note that even we have used 2 availability zones for the cluster control plane, we have configured its nodes in a single availability zone, which means higher communication but less availability.

See also the schema of the YAML file here, and some examples here.

Next, we can install the cluster using the following command:

eksctl create cluster -f ./cluster.yaml

The installation lasts ~20 minutes (go have a coffee...), and it can be tracked in the AWS cloud formation GUI. Once complete, it configures the ~/.kube/config file, so we can connect to the cluster, and run, for example:

$ kubectl get nodes
NAME                             STATUS   ROLES    AGE   VERSION
ip-192-168-1-114.ec2.internal    Ready    <none>   10m   v1.18.9-eks-d1db3c
ip-192-168-12-214.ec2.internal   Ready    <none>   10m   v1.18.9-eks-d1db3c

We can also create the ~/.kube/config on another machine using the command:

aws eks update-kubeconfig --name cdn-middle-1 --region us-east-1

Final Note

I must admit, that compared with Google's GCP kubernetes cloud services, AWS EKS looks very poor, and including minimal support for cluster maintenance.