Why

I’m using Cloudflare as a CDN and DNS provider. For a system with an external IPv4 address that changes daily, I needed a dynamically updated DNS record. There are numerous ways to do DynDNS but I wanted to get into Cloudflare’s API anyway and it turns out that this is, at least in my opinion, much easier to set up than some generic DynDNS package.

How

Getting the script

I’ve forked a script by benkulbertis. The fork does not require a general API token. So you can set up API tokens specifically authorized for what the script needs to do. You can get the script here.

Setting up API tokens

Next, you need to set up the required tokens. The script needs two tokens: one to read DNS records and settings and one to actually edit a DNS zone. To set the tokens up, log in to your Cloudflare account, go to this page and click Create Token. Note, that you can also limit the tokens to a specific domain! This is of course important to know if you have multiple domains in your Cloudflare account and the script shall only read/edit the settings of one of these. You can give your token a custom name and then have to select the permissions it’s supposed to have. These are as follows:

Read token

Type	Resource	Permission
Account	Access: Organizations, Identity Providers, Groups	Read
Zone	Zone Settings	Read
Zone	DNS	Read

Edit token

Type	Resource	Permission
Zone	DNS	Edit

Configuring the script

Now, that you’ve successfully created the API tokens, configure the script by modifying the first four variables accordingly.

Variable	Value
read_token	The read token you’ve just created
edit_token	The edit token you’ve just created
zone_name	The DNS zone your record lies in (e.g. example.com)
record_name	The DNS record (e.g. mysubdomain.example.com)

Moving on

I’ll probably rewrite the script in Python and add an argument parser soon. If you have any other ideas, feel free to drop them here as an issue or pull request.