分类： 系统运维
2008-03-04 16:08:33
Dynamic DNS (DDNS) is an addition to the standard. Dynamic DNS defines a protocol for dynamically updating a DNS server with new or changed values. Prior to DDNS, administrators needed to manually configure the records stored by DNS servers. DDNS allows this to happen automatically for continually changing IP addresses, without the need for human intervention.
In simpler terms, DDNS allows a (FQDN) that doesn't ever change to be associated with a
dynamically assigned IP address that can change quite often. For
example, say you wanted to name your computer
DarthVader.iu.edu but you were required to use
DHCP (as
computers are on the Indiana University network, except for servers,
or mission-critical or special-applications workstations). Even if
you enter DarthVader in the "Computer Name"
field of your
computer properties, DNS servers anywhere would know you only by the
FQDN that is associated with the IP address you are assigned; for
example, at IU, if DHCP gives you an IP address of
156.56.0.1, your computer's name to the entire
Internet
is not DarthVader.iu.edu, but
156-56-0-1.dhcp-bl.indiana.edu. This will be
the case no
matter what you enter into the "Computer Name" field in your settings.
However, DDNS changes that. If you use DDNS, then the DNS servers will
know not to assign you the normal DHCP FQDN, but will properly
associate DarthVader.iu.edu with the IP your
computer
receives every time.
The DDNS service implemented on the IU network works for and Professional, the server versions of Windows 2000, and 2003 Server as well. It will not work for , , 98SE, , 4.0, or XP Home Edition, nor will it work for non-Windows operating systems, such as , , or . This is because IU's DDNS service works through the Active Directory domain controllers, and a computer must be joined to the IU Active Directory to take advantage of it.
If you have a non-Windows operating system, or are not joined to a domain, it is possible to use a third-party DDNS service, such as , , or others. You will have to conduct an online search or contact one of the many providers for instructions on how to use their service with your computer (These providers are named as examples only; UITS does not recommend or endorse any third-party DDNS service.) Keep in mind that although the 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. That would not be the fault of your DDNS service provider; it would be a problem caused by the ISP not updating its DNS tables properly.
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 IT Security Office (ITSO) recommends that you normally run your Windows computer as a member of the Users Group, not as an administrator or a member of the Power Users Group. For more information, see For tasks requiring administrative access, you can gain it quickly using the Windows service. For more information, see
My Network Places
and click
Properties.
Local Area
Connection and click
Properties.
Internet Protocol
(TCP/IP) and click
Properties.
Advanced...
button.
DNS tab. Next to
"DNS suffix for this
connection:", type ads.iu.edu .
Register this
connection's addresses in DNS.
Use this
connection's DNS Suffix in DNS
registration.
OK, then
OK again, and
then
Close.
Now your computer will dynamically register itself with the IU DDNS servers.
Again, this is how you set DDNS up with a Windows computer joined to the IU Active Directory. If you use a third-party DDNS provider, the instructions will almost certainly be far different; in that case, follow your provider's directions rather than the ones here.