Flush DNS for Windows, MacOS, Linux

reset_dns.macos.sh

#!/bin/bash
#
# flushdns
# This script will flush your DNS cache on Mac OS X 10.4 - 10.10.
# The method for doing this chages it seems in every version of OS X, 
# and I can never remember the correct command, so I wrote this script
# and gave it a name I could remeber.
#
# v.2016-02-01 by [email protected]

OSX_VERSION=`sw_vers -productVersion`

echo "Attempting to flush DNS cache"

case $OSX_VERSION in
    # OS X 10.4
    10\.4*)
        lookupd -flushcache
        ;;
    # OS X 10.5 & 10.6
    10\.[56]*)
        dscacheutil -flushcache
        ;;
    # OS X 10.7 & 10.8
    10\.[78]*)
        killall -HUP mDNSResponder
        ;;
    # OS X 10.9
    10\.9*)
        dscacheutil -flushcache
        sudo killall -HUP mDNSResponder
        ;;
    # OS X 10.10 - 10.10.3 - the crappy times
    10\.10|10\.10\.[1-3])
        sudo discoveryutil mdnsflushcache
        sudo discoveryutil udnsflushcache
        ;;
    # OS X 10.10.4 and up -- long live mDBSResponder!
    10\.10\.[4-5])
        dscacheutil -flushcache
        sudo killall -HUP mDNSResponder
        ;;
    # OS X 10.11
    10\.11*)
        dscacheutil -flushcache
        sudo killall -HUP mDNSResponder
        ;;
    # Catch anything else...
    *)
        echo "Sorry, this script is not prepared to handle your version of OS X."
        exit
esac

echo "DNS cache flushed."

exit

reset_dns.unix.sh

#!/bin/bash

echo "Attempting to flush DNS cache"

if [ "$OS" = "Darwin" ]
    then
        MAJOR_MAC_VERSION=$(sw_vers -productVersion | awk -F '.' '{print $2}')
        if [ "$MAJOR_MAC_VERSION" -ge "10" ]
        then
            sudo killall -HUP mDNSResponder
        else
            sudo dscacheutil -flushcache
    fi
fi

if [ "$OS" = "Linux" ]
then
	# Find Unix version and cleares the DNS Cache
	MAJOR_UNIX_NAME=$(lsb_release -i | awk -F ":" '{print $2}')
	if [ "$MAJOR_UNIX_NAME" = "Ubuntu" ]
	then
		sudo /etc/rc.d/init.d/nscd restart
	fi
fi

echo "DNS cache flushed."

# exit

reset_dns.win.bat

echo "Attempting to flush DNS cache"

ipconfig /flushdns
nbtstat -r
netsh int ip reset
netsh winsock reset

echo "DNS cache flushed."
pause