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I'm trying to configure Dynamic DNS client on my router with dd-wrt (v24-sp2) firmware so it would dynamically change IP address in one of the DNS records. Unfortunately I encountered a problem… Here is an example request from their ddclient configuration:<my_login>&tkn=<my_token>&ip=<my_ip>&hosts=<my_record> 

It works if I use it in browser, but in dd-wrt I get this output:

Tue Jan 24 00:36:47 2012: INADYN: Started 'INADYN Advanced version 1.96-ADV' - dynamic DNS updater. 
Tue Jan 24 00:36:47 2012: I:INADYN: IP address for alias '<my_record>' needs update to '<my_ip>' 
Tue Jan 24 00:36:48 2012: W:INADYN: Error validating DYNDNS svr answer. Check usr,pass,hostname! (HTTP/1.1 303 See Other 
Server: cloudflare-nginx 
Date: Mon, 23 Jan 2012 14:36:48 GMT 
Content-Type: text/plain 
Connection: close 
Expires: Sun, 25 Jan 1981 05:00:00 GMT 
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0 
Pragma: no-cache 
Vary: Accept-Encoding 
Set-Cookie: __cfduid=<id>; expires=Mon, 23-Dec-2019 23:50:00 GMT; path=/; 
Set-Cookie: __cfduid=<id>; expires=Mon, 23-Dec-2019 23:50:00 GMT; path=/; 

You must include an `a' paramiter, with a value of DIUP|wl|chl|nul|ban|comm_news|devmode|sec_lvl|ipv46|ob|cache_lvl|fpurge_ts|async|pre_purge|minify|stats|direct|zone_check|zone_ips|zone_errors|zone_agg|zone_search|zone_time|zone_grab|app|rec_se

URL from "Location" works perfectly and parameter "a" is included. What's the problem?

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I'm unclear what you're trying to achieve here, can you be more clear please. – Chopper3 Jan 23 '12 at 15:11
I'm trying change A record in CloudFlare using service in router that manages changing IP addresses and updates domain information dynamically. – Roman Jan 23 '12 at 15:22
I have the same problem but I found something that may help to point us in the right direction. Entering the same URL string in wget exhibits the same problem but firefox does not. – user108628 Jan 28 '12 at 14:04
Did you ever figure this out? – bjtitus Jun 18 '12 at 15:21
Not yet, unfortunately. I wrote a simple python script and using it to update IP manually. – Roman Jun 19 '12 at 6:14
up vote 9 down vote accepted

I don't think you can set it up where DD-WRT calls CloudFlare directly. The way I have it configured is to have DD-WRT call a PHP script on a remote web server, which then detects the client IP and sends the update request to CloudFlare via their API.

DD-WRT DDNS settings

DDNS Service: Custom
DYNDNS Server: <>
Username: <anything>
Password: <anything>
Host Name: <your domain name to update on cloudflare>
URL: /cloudflare_update.php?key=<your secret key>&hostname=


if(empty($_GET['key']) || ($_GET['key'] != "<your secret key>")) die;
$hostname = $_GET['hostname'];
$username = "<>";
$api = "<your cloudflare api key>";
$curl = "$hostname&u=$username&tkn=$api&ip=$ip";
$ch = curl_init($curl);

Instead of using HTTP basic auth I just use a random key.

Make sure you create the DNS entry for the domain name you want to update on CloudFlare; the DIUP action parameter will only update the IP for an entry that already exists.

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Thanks for you suggestion. I had to fix your code a little bit because it couldn't detect my IP address correctly. I used code from this answer to another question. Here's the result - – Roman Jul 20 '12 at 9:09

If you want to execute the update from your router then there is no getting around the fact that you need a little extra 'something' in the middle to convert your call into the CloudFlare format (if only DNS-O-Matic would add them to their supported services...). Rather than have to host an intermediate script yourself you can just use Google AppEngine (which is free) to do this re-posting for you. I use this:

Okay, you still have to call something other than CloudFlare to issue the update but at least you don't need to run an extra host or VPS etc. to do it yourself. It's completely transparent - only problem is that you don't get an errors returned so you need to check it's working yourself. Once it is working it should just run and run.

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I got the error: Error validating DYNDNS svr answer. Check usr,pass,hostname! (HTTP/1.0 302 Found – ayr-ton Dec 2 '14 at 19:55

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