Dynamic DNS

RFC 2136 defines an extension to the DNS to allow updates to the RRsets in a zone. The updates are requested by clients and are dynamically carried out by the primary master nameserver once defined prerequisites are satisifed.

A problem arises when clients attempt to perform dynamic updates in inappropriate circumstances such as updates to a zone for which updates are not permitted.

Both Microsoft Windows 2000 and Apple Mac OS 9 are believed to attempt to use dynamic updates by default. Such clients, when configured to believe they are part of an IE domain, often send update requests to the primary master nameserver for IE. These requests are all refused. Instead of a continually issuing requests that will not be carried out, these clients should be configured not to try dynamic updates.

Below are pointers for how to configure a Windows 2000 and OS 9 client to not use dynamic updates. If you are anyway unsure about whether you need this facility please consult your network administrator.

Windows 2000

The option can be found from:

Click Start -> Settings -> Network and Dialup

View the Properties of Local Area

Select Adapter -> Protocols -> TCP/IP -> Advanced -> DNS

The "Register this name" option box should be clear.

Mac OS 9

In Mac OS 9 a machine tries to register a service name in the DNS whenever Personal WebSharing or Personal FileSharing over TCP/IP is started or stopped. This behaviour is controlled by a Network Services Location Manager (NSL) extension called "DNSPlugin". This extension searches the DNS for services but network services are not allowed to register in the IE zone. The extension should either be reconfigured to refer to your local zone(s) or it can be disabled with the Extensions Manager Control Panel if you do not need its functionality.

The Mac OS 9 instructions are courtesy of Sam Wilson, Computing Services, The University of Edinburgh.