How to flush your DNS cache

Flushing your DNS resolver cache can help resolve many DNS related problems. The TL;DR of flushing DNS is it resets your computer's knowledge of which IPs are associated with which websites/servers, which on occasion can fix weird connection issues. Flushing DNS is different depending on what operating system you use. See below for instructions for Windows, macOS and Linux. In all cases, make sure you have the ability to run commands as an admin on your system. If you do not, contact one of your system admins and ask them to help you.

Windows:

• Open command prompt. You can find it by typing "cmd" into the search bar of the start menu.
• Type the following command into the command window and hit enter:

ipconfig /flushdns

macOS:

• Open System Preferences.
• Navigate to Network > Advanced
• Click 'Renew DHCP Lease' then close System Preferences.
• Run the Terminal app. This is found in Applications > Utilities.
• Type one of the following commands and hit enter. The correct command will depend on your macOS version.

sudo killall -HUP mDNSResponder

dnscacheutil -flushcache

sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

• Type your system password if prompted and hit enter.

Linux:

• Launch Terminal.
• Execute the following commands in Terminal and enter your password if prompted:

sudo /etc/init.d/nscd restart

sudo /etc/init.d/dnsmasq restart

sudo /etc/init.d/named restart
sudo rndc restart
sudo rndc exec
sudo rndc flushname hellabread.net