Solution for dynamic DNS using nsupdate and cgi-bin script.

Instructions:

Create directory /var/www/cgi-bin/nsupdate Copy scripts into it.

Change domain in nsupdate.cgi and nsdelete.cgi

Drop nsupdate.conf in /etc/httpd/conf

Create passwords for names that are allowed to change it's dns A record:

$ cd /et/httpd
$ htdigest -c user.passwd.nsupdate DNS <hostname>

On the machine that has a public dynamic IP or is on a private subnet behind a NAT router with dynamic IP:

crontab -e

0,15,30,45 * * * * curl --digest --user <hostname>:<password> -s https://<YOURWEBSERVER>/nsupdate/nsupdate.cgi > /dev/null