Most users of Cloudflare and Freenom will encounter this “UNKNOWN ERROR” when trying to update IP’s DNS entry using Cloudflare Globe API.
One date I was looking in the cause/fix/workaround for this issue and I found a form posting suggested by a user that they used duckdns. The post explained that using CNAME entry and forwarding their domain to duckdns and updating their IP address with duckdns allow them to work around Cloudflare’s Globe API issue and Freenom domain.
This is how I did.
Here is what you need to be already set up.
Freenom domain added to Cloudflare Free DNS services.
Next, you will need to set up a duckdns account at duckdns.org and create a new subdomain entry that you use to update your IP address when it changes by your ISP.
Next, you need to set up duckdns IP update please flow the website https://www.duckdns.org/install.jsp for your system. I using and pfSence router so I will walk using that method.
Open pfSense and select Services, then Dynamic DNS. Under Dynamic DNS Clients, select Add
Under Service Type, select Custom and leave ALL settings blank other than Update URL. In the Update URL, enter the string below precisely as shown, but substitute your sub-domain and your token (found on the DuckDNS website).
https://www.duckdns.org/update?domains=[SUBDOMAIN]&token=[YOUR TOKEN]&ip=%IP%
In the Result Match field, enter OK. Give the Description like DuckDNS Dynamic DNS and then click Save or Save & Force Update.
As long as the status shows a green checkmark, DDNS is set up and will update moving every time your home IP address changes.
Now we have to forward your Freenom domain to Duckdns using Cloudflare.
Login to your Cloudflare account and select the Freenom domain you want to forward to the Duckdns subdomain address that you have set up.
First, you have to remove any A-type entry for your Freenom domain in Cloudflare and replace it with a CNAME entry. For the Name enter the Freenom domain name and for the Target enter the subdomain with the duckdns.org domain name as shown below.
And as for and subdomain you want to add, just add it like you normally would to Cloudflare.
Now your IP address will be updated every time it changes thanks to Duckdns.org.