Configure CNI

Before we start making changes to VPC CNI, let’s make sure we are using latest CNI version

Run this command to find CNI version

kubectl describe daemonset aws-node --namespace kube-system | grep Image | cut -d "/" -f 2

Here is a sample response

amazon-k8s-cni:1.2.1

Upgrade version to 1.3 if you have an older version

kubectl apply -f https://raw.githubusercontent.com/aws/amazon-vpc-cni-k8s/master/config/v1.3/aws-k8s-cni.yaml

Wait till all the pods are recycled. You can check the status of pods by using this command

kubectl get pods -n kube-system -w

Configure Custom networking

Edit aws-node configmap and add AWS_VPC_K8S_CNI_CUSTOM_NETWORK_CFG environment variable to the node container spec and set it to true

Note: You only need to add two lines into configmap

kubectl edit daemonset -n kube-system aws-node

...
    spec:
      containers:
      - env:
        - name: AWS_VPC_K8S_CNI_CUSTOM_NETWORK_CFG
          value: "true"
        - name: AWS_VPC_K8S_CNI_LOGLEVEL
          value: DEBUG
        - name: MY_NODE_NAME
...

Save the file and exit your text editor

Terminate worker nodes so that Autoscaling launches newer nodes that come bootstrapped with custom network config

Use caution before you run the next command because it terminates all worker nodes including running pods in your workshop

INSTANCE_IDS=(`aws ec2 describe-instances --query 'Reservations[*].Instances[*].InstanceId' --filters "Name=tag:Name,Values=eksworkshop*" --output text` )
for i in "${INSTANCE_IDS[@]}"
do
	echo "Terminating EC2 instance $i ..."
	aws ec2 terminate-instances --instance-ids $i
done