Web service for Dynamic DNS service

Posted by ads' corner on Saturday, 2014-04-12
Posted in [Software]

Last in my small series about running your own Dynamic DNS service: how to support clients which can’t use the nsupdate tool directly.


  • A webserver with a scripting language
  • A dumb client which a browser or browser emulation (like lynx or curl)

On the server side you need a little script, plus the dns-update.pl from this posting plus the Bind key for the zone you want to update. Here is the script, let’s say the name is update-zone.php:


if ($_GET['key'] == 'cryptic_key') {
    system("/srv/www/updates.domain/dns-update.pl /srv/www/updates.domain/entry1-transfer.key entry1.updates.domain " . $_SERVER['REMOTE_ADDR']);


The cryptic_key should be a random value, it’s only required to identify the client. Then the dns-update.pl script is executed with the Bind key, the hostname which should be updated and the IP address of the client. Note: if you want the client to supply it’s name as well (the second parameter), make sure you sanitize the input.

Now all the client has to do is open a website from time to time:

lynx -source -dump 'http://<webserver>/update-zone.php?key=cryptic_key'

It’s a good idea to protect the website with https as well.

Categories: [Software]