arnd / hello-aws

Playing with AWS

Hello AWS!

When launched, this AMI serves this Readme via HTTP. It is based on ubuntu 20.04 and uses nginx to service user requests.

Instructions to re-create this AMI

This AMI was created by deploying an ubuntu 20.04 instance within a VPC with terraform. Below you find instructions to re-deploy it from the Git Repository

Prerequisites

• Terraform >= v0.12.69
• AWS Credentials with EC2 permissions (e.g. AmazonEC2FullAccess)
• markdown (http://daringfireball.net/projects/markdown/)
• AWS CLI

Deploy new Instance and create Public AMI

1. Setup credentials aws configure (per default terraform will use AWS Shared Credentials File)
2. Setup terraform working directory: terraform init
3. Deploy new Instance and AMI terraform apply
4. Visit the new Instances URL and check if the Content is delivered fine (check terraform output)
5. Tear-down infrastructure terraform destroy
6. Make a copy of the terraform created AMI (e.g. via aws ec2 create-image --instance-id <REPLACE-WITH-INSTANCE-ID> --name $(date -I)-aws-hello)
7. Make AMI public (e.g. via aws ec2 modify-image-attribute --image-id ami-0db087fa93dde7690 --launch-permission "Add=[{Group=all}]")

Terraform Dry-run

1. terraform init -backend=false
2. terraform validate

Lessons learned

• AWS accounts which were created before 2013-12-04 may not allow a default VPC in a region. (EC2-Classic)
• Letsencrypt will not hand out SSL certificates for default AWS public DNS names (.compute.amazonaws.com), because these are ephemeral names.
• Terraform's aws_ami_from_instance might create the AMI before cloud-init went through, which then would require continue bootstrapping when AMI is launched
• Terraform's file() function requires the file referenced to be there during HCL parsing
• AWS Cli's ec2 create-image does not seem to allow to specify tags (e.g. via --tag-specifications)