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How often does the DNS cache clear?

How often does the DNS cache clear?

How often does the DNS cache clear on a Windows 7 machine?

Asked by: Guest | Views: 69
Total answers/comments: 2
Guest [Entry]

"The DNS cache doesn't ever flush, unless you explicitly tell it to or you make a DNS/networking related configuration change. DNS records have a Time To Live (TTL) value associated with them which tells a DNS cache how long the particular record is good for. Records in the cache are kept for their TTL, then re-queried.

On a Windows machine you can see a list of all the records in your cache along with their TTL by executing the following command at the command prompt:

ipconfig /displaydns

You can force a flush of all cached DNS records using the following command:

ipconfig /flushdns

For more info:

Wikipedia article on DNS and TTLs"
Guest [Entry]

"According to: Reduce DNS Client Cache in Windows Server 2012 R2
Instead of MaxCacheEntryTtlLimit you should modify maxcacheTTL. It works for Windows 8 too.

Determines how long the Domain Name System (DNS) server can save a record of a recursive name query.
If the value of this entry is 0x0, the DNS server does not save any records."