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How to flush DNS cache in Mac, Linux and Windows

We sometime require to flush the system's DNS cache to resolve  issues raised around dns. The following section provides you the information about how to do it on Mac, Linux or Windows

Flushing DNS cache on Mac OS X.
  • Launch Terminal application and run the command ( On Leopard,Snow Leopard and Above)
           $ dscacheutil -flushcache
  • Or if your operating system is Tiger, then 
           $ lookupd -flushcache

Flushing DNS Cache in Linux.
  •  In Linux, the "nscd" daemon/service is responsible for managing the dns related operations. To flush the dns cache on linux , simply restart the "nscd"  service with command " /etc/init.d/nscd restart " in terminal with root privileges.
Flushing DNS Cache in windows.
  • On windows , to flush the dns cache - open command prompt and run the below command. 
        C:>ipconfig /flushdns

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