pfSense

It seems DNSimple recently updated their web server to use HTTP/2 for their API. The curl response handling code in the Dynamic DNS client uses a simple regex to look for ` 200 OK `, which no longer matches the success response from DNSimple.

DNSimple's API sends back a response like:

HTTP/2 200 \r\n
server: nginx
...

The response regex used to detect "success" for most clients in the DNSimple lib use this regex: /\s200\sOK/i

The php curl library has a function to extract the status code, it's probably safer to use that everywhere instead.

$code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
if ($code == "200") {
  // ...
}