How To Use a Domain Name with a Dynamic IP Address (Dynamic DNS)

Introduction

A domain name is simply a string of alphanumeric characters, such as "www.example.com", that is associated with a particular IP address, such as 101.18.233.4. Domain names make it easier to remember the location of a Web site or other resource on the Web, since words are easier to remember than numbers. When you enter a domain name in, for example, your browser's address bar, your computer asks a Domain Name System (DNS) server on the Internet for the IP address associated with that domain name. When it gets the IP address, your computer then uses it to find the Web site you want.

If you are running a Web site on Square One, clearly it would be good to be able to give Square One its own domain name: when you tell your friends or customers about your Web site, it's much nicer to give them an address like bob.mysquareone.net instead of a bunch of numbers. The problem is that the DNS system only works when the computer or server you want to assign a domain name has a fixed, unchanging IP address. However, most residential and some small business ISP accounts—the kind of Internet connections that most people use with Square One—only provide a dynamic IP address, meaning that Square One's IP address can change at any time. This doesn't matter when you are using the Internet normally, since your IP address is unlikely to change in the short time it takes for you to read a Web page or download a file. But it's a serious problem when you're running a server, because other computers on the Internet can't find you if your IP address keeps changing.

The solution is a service known as Dynamic DNS, or DDNS for short. DDNS lets you give a domain name to your server—and keep it valid—even if your server's IP address changes periodically.

How Dynamic DNS works

1. You create an account with a DDNS provider, such as DynDNS. At this time, you choose the domain name that you want Square One to use, and you register Square One's current IP address to that domain name. The DDNS provider then injects the new domain name / IP address association into the DNS system.
2. Whenever Square One's IP address changes, a background process on Square One notices the change and registers the new IP address with the DDNS provider's server.
3. The DDNS server updates the domain name / IP address association on the DNS system, so that the domain name now points to the new IP address.

Quad Micro Works' Dynamic DNS service

When you register your Square One on this web site, you have the option of choosing a domain name to use with our free DDNS service. This basic service allows you to use a domain name in the form of [subdomain].mysquareone.net. (For example, bob.mysquareone.net.)

Third-party Dynamic DNS providers supported by Square One

In addition to QMW's DDNS service, Square One knows how interface with several third-party DDNS providers, so you have a choice of which provider to sign up with. Providers that offer basic DDNS service at no cost are noted. Here is the list of supported providers, in alphabetical order:

* Some limitations apply.

How to set up Square One to use Dynamic DNS with DynDNS

Below are step-by-step instructions for setting up a DDNS account with DynDNS (one of the leading DDNS providers) and setting up Square One to report IP address changes to DynDNS. Each DDNS provider's setup process is somewhat different, but after reading these directions you should be able to figure out how to set up DDNS service with any provider.

Setting up your DynDNS account

1. Point your browser to http://www.dyndns.com/account/create.html.
2. Fill in the account sign-up form. You will be send a confirmation email with a link to confirm account sign-up.
3. Log in to DynDNS using your account name and password.
4. Click Account, click My Services, click Add Host Services, and then click Add Dynamic DNS Host.
5. Enter the desired hostname and select one of the domains from the drop-down menu. (Note: If you want to use your own domain name, such as "example.com", you will need to sign up for Custom DNS, which is an extra-cost service.)
6. Enter Square One's current WAN IP address. You can determine what the current WAN IP is on the System Status page of Square One's admin interface (from the admin home page, click Show Status).
7. Click Add Host.

Now, you need to set up Square One to report IP address changes to DynDNS.

Setting up Square One to report IP address changes to DynDNS

1. Point your browser to Square One's admin interface (by default, http://192.168.1.1:8090/).
2. Click Networking, and then on the side menu click Dynamic DNS.
3. Select the Enable option for Enable Dynamic DNS.
4. In the Service provider menu, select DynDNS [dyndns.org].
5. In the Host name box, enter the entire domain name you selected when you signed up for DDNS service (step 5 in the previous instruction list). For example, "jsmith.dyndns.org".
6. Enter your DynDNS username and password, and then click Apply.

That's it. From now on, you can reach your Web site (or other services) on Square One from anywhere on the Internet, even if you don't know what Square One's IP address is. All you and your friends and customers need to remember is your domain name.