Cloudflare Dynamic DNS backend for Inadyn

Why?

I have a Unifi Dream Machine and I want to update my home dns when my ip changes. The Unifi controller dynamic dns service doesn't support Cloudflare as a service. I hope this is a temporary solution as the version 2.6 of Inadyn already natively support cloudflare.

Create and deploy the worker

We'll use cloudflares wrangler cli to build and deploy the service worker

Install wrangler

npm install -g @cloudflare/wrangler

Setup you account

wrangler config

Deploy the worker.

You need to add your account id to the provided wrangler.toml file. You can get it from the Cloudflare manage worker page (on the sidebar)

Enable your workers subdomain

wrangler subdomain <worker-subdomain>

Publish the worker

wrangler publish

Setup Unifi controller

Go to your unifi controller Dynamic Dns section and setup the following

service: choose anything, it doesn't matter
hostname: the name of the record you want to update (e.g. subdomain.mydomain.com)
username: the name of the zone where the record is defined. (e.g. mydomain.com)
password: a Cloudflare api token with dns:edit and zone:read permissions
server: the Cloudflare Worker DNS plus the path dyndns.<worker-subdomain>.workers.dev/update?hostname=%h&ip=%i

Note: you might need to escape an extra slash between the hostname of your worker and the path due to a bug in the controller ui. dyndns.<worker-subdomain>.workers.dev/\/update?hostname=%h&ip=%i At least as of UDM controller version 6.1.71 you no longer need this

Debugging

You can login into you UnifiOS terminal and run the following command to se how the configuration is working.

inadyn -1 -l debug -n -f /run/inadyn.conf

You can also look at the logs from the background process from the UDM