转自：
https://blog.csdn.net/Qin605/article/details/78444888

Windows:

ipconfig /flushdns

Debian/Ubuntu:

sudo /etc/rc.d/init.d/nscd restart

Linux with systemd:

sudo systemctl restart network.service

Fedora Linux:

sudo systemctl restart NetworkManager.service

Arch Linux/Manjaro with Network Manager:

sudo systemctl restart NetworkManager.service

Arch Linux/Manjaro with Wicd:

sudo systemctl restart wicd.service

Mac OS X:

sudo dscacheutil -flushcache;sudo killall -HUP mDNSResponder