DNS (Domain name server) service caches the name resolutions made by your computer to speed up the internet browsing. For example you visited google.com for the very first time using your computer/laptop it will generate a query to other server to know the IP (Internet Protocal) address of google.com ones it get resolved. it will store the ip address & domain name in cache so that it can be served immediately when u request the same domain name again.
For some reasons you might want to clear your cache files, like you just changes your own website host name or experiencing dome problem with other sites. you can get rid of it by flushing the DNS cache.
How to Flush DNS in Windows
If you want to flush dns cache in windows operating system, open command prompt (CMD) and type this command “ipconfig /flushdns” and hit enter.
As you can see in the above screen shot, using that using that comman we flushed complete DNS cache files. If you want you can use this command “ipconfig /displaydns” to view the Domain Name Server (DNS) cache logs.
How to Flush DNS in Mac OS X
If you’re a Mac OS X leopard user, use the command “dscacheutil -flushcache” to clear full DNS cache.
bash-2.05a$ dscacheutil -flushcache
If you’re a Mac Os X version 10.5 or before version user, Use the command “lookupd -flushcache” to clean DNS cache.
bash-2.05a$ lookupd -flushcache
How to Flush DNS in Linux
In Linux, the nscd daemon manages the DNS cache. To flush the DNS cache, restart the nscd daemon. To restart the nscd daemon, use the command `/etc/init.d/nscd restart`.
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