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        How To Disable Caching Of A DNS Record

Section(s): DHCP and DNS, Admin
Published on Mar 01, 2011.
Last Modified on Jan 09, 2010.
Last Modified by Nirmal Sharma.
Rated 3 out of 5 based on 2 votes.

This article explains how you can disable caching of DNS Resource Records for a DNS Server.

By default Microsoft DNS Servers cache a record for 1 day. In some cases, you might need to disable this functionality for a DNS Server. To disable this behaviour, you can modify the below mentioned registry entry:

KEY Name: HKLM\System\CurrentControlSet\Services\DNS\Parameters
Entry Name: MaxCacheTtl
Type: REG_DWORD
Value: 0x15180 (this is the default value)

To disable the caching completely on DNS Server, set the value of MaxCacheTtl to 0x0. The DNS Server saves the records in memory area so that it can respond quickly to the Client DNS Queries for the same name. Records are deleted from the cache as per the value defined in the MaxCacheTtl registry entry. The value of this entry overrides the TTL Value set on the Resource Record.

About Nirmal Sharma

Nirmal is a Microsoft MVP in Directory Services and working as a Technical Architect/Consultant. He has been involved in Microsoft Technologies since 1994 and followed the progression of Microsoft Operating Systems and software. He is specialized in Directory Services, Microsoft Clustering, SQL, MOM, Exchange and Citrix. In his spare time, he likes to help others and write "internal" technical articles, white papers and tips on various Microsoft technologies. You can contact him at nirmal_sharma@mvps.org.