terraform-route53-ddns-updater

Make yourself a little DDNS service with the power of amazon route53 and terraform

How it works

This little terraform script looks up your current external IP address from https://icanhazip.com and sets it to the route53 record of your choice. Just throw it in a scheduled task and you have a DDNS service.

Setup

IAM

Find the route53 zone_id for the zone in question. You'll need this in two places. First, for the IAM policy. Create a new one that looks like this, but substitute ZONE_ID with yours.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "VisualEditor0",
            "Effect": "Allow",
            "Action": [
                "route53:GetChange"
            ],
            "Resource": "*"
        },
        {
            "Sid": "VisualEditor1",
            "Effect": "Allow",
            "Action": "*",
            "Resource": "arn:aws:route53:::hostedzone/ZONE_ID"
        }
    ]
}

Attach the new policy to an IAM user, and make sure you have the credentials on hand, because you'll need them for the configuration in the next step.

Terraform variables

Copy variables.tfvars.json.example to variables.tfvars.json.

Replace all the values. aws_access_key, aws_secret_key, and zone_id you should have on hand from the last step. domain_name is the address that you want to use for DDNS. Note that the domain name needs to be a subdomain (or equal to, as in the root record) of the zone that you've selected with the zone id.

Try it out

Use these commands to see if your configuration is set up properly:

terraform init -get=true -get-plugins=true -upgrade=true
terraform plan -var-file variables.tfvars.json

Add a scheduled task

If everything looks good, you'll want to run terraform apply -var-file variables.tfvars.json -auto-approve with your operating system's scheduler.

• Windows: https://superuser.com/a/403597/173153 in combination with the provided batch file: apply.bat
  • TODO: If anyone knows how to make this log somewhere useful on windows, let me know or submit a pull request
• UNIX: Add something like this to your crontab */5 * * * * /home/user/terraform-route53-ddns-updater/apply.sh