Delegated Dynamic DNS

DDDNS - Delegated Dynamic DNS - ensures that if your dynamic DNS name resolves, then it is because your server is present (i.e. dialled out or connected). Your DNS name is delegated to your own name server at your current IP address. If your server is not present, or if another server has taken your former IP address, then the lookup fails, and the name does not resolve. This is not a problem, because it indicates (correctly) that you are not there.

Technical details
Dynamic DNS (DDNS) is a well-worn technique for associating a DNS name with a dynamic IP address, usually ADSL, but occasionally dial-up as well. With DDNS, what happens if your machine is not connected for some time? A person visiting your web site may see another site. Mail to your domain may be rejected with a rude message ("relay access denied") (or, even worse, it may be accepted).

DDDNS allows you to run a web site and mail server on a dynamic address with the assurance that if your link is down your name will also be down. Having a reliable DNS name means that you can do all the things you should require a static IP address for:

Miscellaneous notes

Audience: Wireless and ADSL users. Dial-up users may be interested too.
System requirements: bind 9, nsupdate and `host'. netdate is recommended if you are not keeping your clock in sync with ntpd
Language: bash
Source license: GPL

Related services
If you are interested in this software, you may like to send us a large payment, or make use our related services:

*Free? Yes, free, as in beer. We know that a good proportion of people will (a) buy the backup mail spooling offer and (b) pay us to set it up and (c) DNS is not really bandwidth intensive.

Download and documentation

Automatic account failover
We have included our failover scripts to handle multiple simultaneous pppoe connections. This is to overcome the 3GB traffic quota offered in South Africa.

There are a number of complications that the scripts take care of -