What is Dynamic DNS (DDNS), and how do I set it up at IU?

Dynamic DNS (DDNS) is an addition to the DNS standard. Dynamic DNS updates a DNS server with new or changed records for IP addresses without the need for human intervention. This allows a fully qualified domain name (FQDN) that never changes to be associated with a dynamically assigned IP address that can change quite often.

For example, suppose you want to name your computer DarthVader.ads.iu.edu but are required to use DHCP. Even if you enter DarthVader in the "Computer Name" field of your computer properties, DNS servers anywhere would know you only by the FQDN associated with the IP address you're assigned. At Indiana University, if DHCP gives you an IP address of 156.56.0.1, your computer's Internet name would not be DarthVader.ads.iu.edu, but 156-56-0-1.dhcp-bl.indiana.edu. However, if you use DDNS, your computer's IP address will be properly associated with DarthVader.ads.iu.edu .

At IU, DDNS works for Windows Vista, XP Professional, Windows 2000, and the server versions of each (2000, 2003, 2008). It will not work for the Home editions of Vista or XP, versions older than 2000, or non-Windows operating systems, such as Mac OS X, Linux, or BSD. If your operating system is not supported, or if you cannot join the ADS domain, you can use a third-party DDNS service, such as Dynamic Network Services, Inc. or PlanetDNS. For a comprehensive list of DDNS providers, see DNS Lookup's Dynamic DNS Providers List. UITS does not recommend or endorse any third-party DDNS service.

Although DDNS is an official addition to the DNS standard, not all ISPs refresh their own DNS servers' data often enough to reflect daily changes, so some users may still run into trouble accessing your DDNS-configured FQDN. This is not the fault of your DDNS service provider, but a problem caused by the ISP not updating its DNS tables quickly enough.

To set up your Windows computer to use Indiana University's DDNS service, follow these steps while logged in as an administrator:

Note: At Indiana University, the University Information Security Office (UISO) recommends that you normally refrain from running your Windows computer as an administrator. For more, see What is the principle of least privilege?

Windows 7 and Vista

1. From the Start menu, click Network.
   
   
2. From the toolbar of the window that opens, click Network and Sharing Center.
   
   
3. On the left, click Change adapter settings (in Windows 7) or Manage network connections (in Vista).
   
   
4. Right-click Local Area Connection, and click Properties.
   
   
5. Select Internet Protocol 4 (TCP/IPv4), and click Properties.
   
   
6. Click Advanced... .
   
   
7. Click the DNS tab. Next to "DNS suffix for this connection:", type ads.iu.edu .
   
   
8. Check Register this connection's addresses in DNS.
   
   
9. Check Use this connection's DNS Suffix in DNS registration.
   
   
10. Click OK, then OK again, and then Close.

Windows XP

1. Right-click My Network Places, and choose Properties.
   
   
2. Right-click Local Area Connection, and click Properties.
   
   
3. Select Internet Protocol (TCP/IP), and click Properties.
   
   
4. Click Advanced... .
   
   
5. Click the DNS tab. Next to "DNS suffix for this connection:", type ads.iu.edu .
   
   
6. Check Register this connection's addresses in DNS.
   
   
7. Check Use this connection's DNS Suffix in DNS registration.
   
   
8. Click OK, then OK again, and then Close.

Now your computer will dynamically register itself with the IU DDNS servers.