do-dyndns is a simple dynamic DNS client for DigitalOcean. It can update one or
more DNS records on your DigitalOcean-managed domains with the public IP address
of a client host.
For example, let’s assume you have a managed domain example.com in your DigitalOcean account
and a host named foo in your homelab. If such host has an external public IP provided by your ISP,
then you could run do-dyndns periodically on foo to keep a subdomain record foo.example.com
pointed to the actual public IP.
Download the appropriate binary for your platform from Releases and copy it to any directory in your PATH as do-dyndns.
Copy the example configuration file config.json.example to $HOME/.config/do-dyndns/config.json.
Make sure to create first the $HOME/.config/do-dyndns directory or, alternatively, you can use a more traditional $HOME/.do-dyndnsrc.json file.
Edit config.json and set the following fields:
"token"(mandatory): Your DigitalOcean Personal Access Token. It must have Write scope."log"(optional): the full path to a log file."records"array (mandatory): an array of subdomains to be dynamically updated.
do-dyndns will log all its activity to the log file when run as a cron job.
The log file is not used when running in an interactive shell. It is not used either
when running as a systemd scheduled task, because stdout is logged automatically
in this case. If log is not provided, it will default to $HOME/.cache/do-dyndns/out.log.
For each item in records, you need to set:
"type":"A", IPv4 DNS “A” record, the only supported type for now."subdomain": a fully qualified subdomain name to be dynamically updated with the current public IP of the client host.
You can run do-dyndns as a cron job. All activity will be logged to the log file.
(see the configuration file above.)
Alternatively, you can install do-dyndns as a systemd timer. Note that do-dyndns will
not log its activity to the log file when running as a systemd timer.
This is because systemd itself takes care of logging; use journalctl to query it.
For further information on systemd timers, see the excelent ArchWiki documentation. (Note that this documentation is not specific to Arch Linux—it applies to any systemd-based Linux distro.)
I tested it on Ubuntu 22.10, Fedora 37 and macOS Monterey 12.6.7. Note that there are no special requirements for Linux or macOS, so that it should work on any reasonably modern Linux distro or macOS release.
The Linux x86-64 binary should work on Windows 10/11 using WSL 2 (Windows Subsystem for Linux). Unfortunately, I don’t have access to a Windows system, so I can’t confirm this.
do-dyndns is written in Go 1.19. The source code is entirely contained in main.go.
Pull requests are welcome.
I wrote a small Makefile to help me with routine tasks.
To update all Go dependencies, and update go.mod and go.sum:
$ make dependencies
To run golangci-lint locally (you need golangci-lint installed):
$ make lint
To build the binary for your development platform:
$ make build
To install the binary in your default path:
$ make install
To create a new GitHub Release using the latest tag (this requires the GitHub CLI):
$ make releases