A little golang application to register a DNS record with Route53 for a machine behind NAT on a dynamic IP. Handy for running a home server.
This application sends a DNS query for OpenDNS's myip.opendns.com subdomain, which will respond with the A Record for your current public IP (an alternative method could be to use a HTTP query to https://diagnostic.opendns.com/myip).
The application will cache the result in a cache file in /tmp and compare it between runs. If the file changes (or is missing), it'll then attempt to upsert an A Record to Route53 for the configured domain and the new IP address.
The dynamic-dns-route53 application should respect all the typical ways your AWS credentials can be configured (ex. files at ~/.aws/credentials, IAM role, etc). The application will neeed the route53:ChangeResourceRecordSets permission.
$ ./dynamic-dns-route53 -help
Usage of ./dynamic-dns-route53:
-name string
domain name
-path string
path to cache file (default "/tmp/.dynamic-dns-route53.cache")
-server string
resolver (default "resolver1.opendns.com")
-target string
lookup target (default "myip.opendns.com")
-ttl int
TTL in seconds (default 60)
-zoneId string
Route53 zone ID