Rolling Update with Terraform

This code is just a representation on how you could apply rolling update to yours EC2 instances. Do not use it in production.

terraform --version
Terraform v0.13.1

packer --version
1.6.0

Instructions:

Create the first image

cd packer
packer build .

Apply the terraform

cd ..
terraform init
terraform apply

Check the current color of the page

In another terminal:

while true; do
curl $(terraform output lb_dns)
sleep 1
done

Create another image with a different color

cd packer
packer build -var 'color=blue' .

Apply the new image version

cd ..
terraform apply

Clean up

terraform destroy

Deregister AMI from the console.