The Demand-Dial Interface Does Not Disconnect When Network Address Translation Is Installed (278880)

The information in this article applies to:

Microsoft Windows Server 2003, Enterprise Edition
Microsoft Windows Server 2003, Standard Edition
Microsoft Windows Small Business Server 2003, Premium Edition
Microsoft Windows Small Business Server 2003, Standard Edition

This article was previously published under Q278880

SYMPTOMS

A demand-dial interface that is used as a network address translation (NAT) and a public interface may not hang up; or, the demand-dial interface may be initiated automatically from a Windows Server 2003-based Routing and Remote Access server that is a domain controller and runs the DNS Server service.

CAUSE

This behavior can occur because the DNS Proxy option is enabled for NAT. The modem continues to dial because of the traffic that is being generated by the DNS server.

RESOLUTION

To resolve this behavior, do not enable the DNS Proxy option in NAT on the domain controller. To disable the DNS Proxy option:

From the Routing and Remote Access service Microsoft Management Console (MMC) snap-in, expand the IP Routing section.
Right-click Network Address Translation (NAT), and then click Properties.
On the Name Resolution tab, click to clear the Clients using Domain Name System (DNS) check box.
Click OK.

This option can also be disabled from a command prompt: By means of the Netsh.exe program, use the netsh routing ip dnsproxy uninstall command.

MORE INFORMATION

Even if you disable the DNS Proxy option, other types of network traffic may cause the demand-dial interface to connect. One possible solution to prevent sporadic dialing of demand-dial interfaces is to apply Internet Protocol (IP) filters. If you apply a filter, you can enable only the traffic that you want, to use the demand-dial interface, and you can prevent the filtered traffic from initiating the demand-dial interface.

Modification Type:	Minor	Last Reviewed:	1/20/2006
Keywords:	kbprb KB278880