How to flush dns in ubuntu 12.04? [duplicate]

Solution 1:

According to this SU answer "How to clear DNS cache in Ubuntu?", Ubuntu by default does not provide DNS cache service. But if you have one that you installed manually, you could usually restart those services to clean the cache. Here are some examples ^(source):

• Run this command to flush DNS:

  sudo /etc/init.d/dns-clean restart
  

• Followup the above command with this:

  sudo /etc/init.d/networking force-reload
  

• To flush nscd DNS cache:

  sudo /etc/init.d/nscd restart
  

• To flush dnsmasq DNS cache:

  sudo /etc/init.d/dnsmasq restart
  

• If you use BIND this should flush DNS:

  sudo /etc/init.d/named restart
  

  or

  sudo rndc restart
  

  or

  sudo rndc exec
  

  BIND (>= v9.3.0) supports flushing records from a particular domain and also the lan and wan views.^source Examples:

     sudo rndc flush
  
     sudo rndc flushname askubuntu.com
  
     sudo rndc flush lan
  
     sudo rndc flush wan
  

Solution 2:

Install nscd using the following command if not yet

sudo apt-get install nscd

Flush DNS Cache in Ubuntu by restarting the nscd

sudo /etc/init.d/nscd restart