Recently I ran into a problem while working with Amazon EC2 servers. Servers without dedicated elastic IP addresses would get a different IP address every time they were started up! This proved to be a challenge when trying to SSH in to the servers.

How can I have a dynamic domain name that always points to my EC2 server?

Amazon’s Route53 came to mind. Route53, however, does not have a simple way to point a subdomain directly to an EC2 instance. You can set up load balancers between Route53 and your instance, but that’s a hassle. You can also set up an elaborate private network with port forwarding – yuck.

I wanted a simple way to set a Route53 subdomain’s A record to point to an EC2 instance’s public IP address, on startup.

Enter go-route53-dyn-dns. This is a simple Go project that solves this problem. It is a small binary that reads a JSON configuration file and updates Route53 with an EC2 instance’s public IP address.

Included in the GitHub README.md file is how to set everything up.

The project is here: go-route53-dyn-dns.