Flushing the DNS in Ubuntu 16.04

flush-dns.sh

#!/bin/bash

# NB: First install nscd with sudo apt-get install nscd

# run this command to flush dns cache:
sudo /etc/init.d/dns-clean restart
# or use:
sudo /etc/init.d/networking force-reload
# Flush nscd dns cache:
sudo /etc/init.d/nscd restart
# If you wanted to refresh your settings you could disable and then run
sudo service network-manager restart

echo "DNS Flushed!";

# Output:

# craig@laptop:~$ sh Desktop/Scripts/flush-dns.sh 
# [sudo] password for craig: 
# [ ok ] Reloading networking configuration (via systemctl): networking.service.
# [ ok ] Restarting nscd (via systemctl): nscd.service.
# DNS Flushed!