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I was reading a part of DNS cache locking. I can't find much information about how this works with DNS dynamic updates. <br />
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In Technet <br />
'Cache locking is configured as a percent value. For example, if the cache locking value is set to 50, then the DNS server will not overwrite a cached entry for half of the duration of the TTL. By default, the cache locking percent value is 100. This means that cached entries will not be overwritten for the entire duration of the TTL. The cache locking value is stored in the CacheLockingPercent registry key. If the registry key is not present, then the DNS server will use the default cache locking value of 100.'<br />
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So, the default cache locking was always 100%. So, until TTL of the resolved DNS record passes, the cached DNS record will not be overwritten. If then, when a internal device changes its record, what happens? Will DNS server returns the old DNS record of the device to requests? <br />
<br />
Can anyone explain how DNS caching and dynamic update work together to respond correct DNS information to requests? <br />
<br />
Thanks.
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I was reading a part of DNS cache locking. I can't find much information about how this works with DNS dynamic updates. 

In Technet 
'Cache locking is configured as a percent value. For example, if the cache locking value is set to 50, then the DNS server will not overwrite a cached entry for half of the duration of the TTL. By default, the cache locking percent value is 100. This means that cached entries will not be overwritten for the entire duration of the TTL. The cache locking value is stored in the CacheLockingPercent registry key. If the registry key is not present, then the DNS server will use the default cache locking value of 100.'

So, the default cache locking was always 100%. So, until TTL of the resolved DNS record passes, the cached DNS record will not be overwritten. If then, when a internal device changes its record, what happens? Will DNS server returns the old DNS record of the device to requests? 

Can anyone explain how DNS caching and dynamic update work together to respond correct DNS information to requests? 

Thanks.

DNS cache locking and dynamic DNS record update

The Domain Name System (DNS) is a hierarchical, globally distributed system responsible for associating the name of a computer, service or other resource into an IP address for connecting to the Internet or a private network. Most prominently, it translates domain names to the numerical IP addresses needed for the purpose of computer services and devices worldwide.

Windows Server 2008 and Windows Server 2008 R2, based on the Microsoft Vista codebase, is the last 32-bit server operating system released by Microsoft. It has a number of versions, including including Foundation, Standard, Enterprise, Datacenter, Web, HPC Server, Itanium and Storage; new features included server core installation and Hyper-V.

Windows Server 2008

Windows Server 2012 is the server version of Windows 8 and the successor to Windows Server 2008 R2. Windows Server 2012 is the first version of Windows Server to have no support for Itanium-based computers since Windows NT 4.0. Windows Server 2012, now in its second release (Windows Server 2012 Release 2) includes Foundation, Essentials, Standard and Datacenter, and does not support IA-32 or IA-64 processors.