DNS cache locking and dynamic DNS record update
Posted on 2014-11-25
I was reading a part of DNS cache locking. I can't find much information about how this works with DNS dynamic updates.
'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?