Self-hosted Dynamic DNS for DreamHost Users

It's simple to run your own dynamic DNS server in your DreamHost account if
you use DreamHost to manage your domain names. 

 * Check out this directory to somewhere in your DH account that's publically
   accessible.

 * Get an API key from: https://panel.dreamhost.com/index.cgi?tree=home.api
   for "All dns functions". Put that key in ~/.ddns-api-key

 * Create a htpassword file with hostname you want to use as the username:
    htpasswd -c ~/.ddns.htpasswd home.example.com

 * Update the .htaccess file in this directory so that the AuthUserFile 
   points to your home directory:
    AuthUserFile /home/myusername/.ddns.htpasswd

 * Configure your router to talk to the new server. In DD-WRT choose,
   DDNS Service = Custom
   DYNDNS Server = the hostname that this script runs on (eg: www.example.com)
   URL = the path on this server, plus "?" (eg: /ddns/?)
   User Name & Host Name = the dynamic DNS host name (eg: home.example.com)
   Additional DDNS Options = --dyndns_system dyndns@dyndns.org
     This script implements the dyndns protocol so tell the router to use that.

NOTE: DreamHost DNS entries have a TTL (time-to-live) of 4 hours so they
won't be quite as dynamic as a real DynDNS service.

References:
  http://wiki.dreamhost.com/API/Dns_commands
  http://www.dyndns.com/developers/specs/