Flushing dns cache mac os

How to Flush DNS Cache in macOS, Windows, & Linux

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DNS cache can be corrupted for a number of different reasons, including network attacks or viruses. When that happens, IP address mapping becomes corrupted for certain popular websites.

For example, instead of going to www.facebook.com, your browser may redirect you to an IP address of a malicious website that an attacker inserted in your computer’s DNS records. Or, you may get a large number of 404 errors.

Clearing DNS cache deletes all saved DNS lookup information. Your computer then gets updated data from DNS servers next time it sends a lookup request. Learn how to flush DNS on in macOS, Windows, & Linux below.

What is DNS Cache?

Linux, Windows, and macOS save name resolution information in the form of DNS cache. This speeds up project load times since the cache contains IP addresses for the queried domains. Instead of having to reroute to DNS servers, the system answers queries from the cache.

The DNS cache contains the following information:

• Resource data
• Record type
• Record name
• TTL (time to live)
• Class
• Resource data length

How To Flush DNS Cache on Mac

There are a few different commands to use for flushing DNS cache on OS X and macOS depending on the version you are running.

As the procedure is the same on all versions, this article details how to clear DNS on macOS Mojave (10.14) and then list the commands for other versions in a table.

Flush DNS on macOS Mojave (version 10.14)

To clear DNS cache on macOS Mojave, use the Terminal application:

1. Run terminal.app using your preferred method. You can launch the app from Applications -> Utilities or press Command + Space to launch Spotlight and search for Terminal.
2. Type in sudo killall -HUP mDNSResponder and hit Return on your keyboard.
3. Enter the administrator password for the account in question and hit Return.

There is no notification when the process finishes. However, you can append another command to change that.

Note: If you want to hear an audio notification after the DNS flush is complete, type say some text after the first command. For example:

Flush DNS Commands on Older macOS and Mac OS X Versions

The table below lists the commands for clearing the DNS cache on most macOS and Mac OS X versions. You can copy and paste them directly from the table into your terminal.

Mac OS X or macOS version	Terminal Command
Mojave (version 10.14) High Sierra (version 10.13) Sierra (version 10.12) Mountain Lion (version 10.8) Lion (version 10.7)	sudo killall -HUP mDNSResponder
El Capitan (version 10.11) Mavericks (version 10.9)	sudo dscacheutil -flushcache sudo killall -HUP mDNSResponder
Yosemite (version 10.10)	sudo discoveryutil mdnsflushcache sudo discoveryutil udnsflushcaches
Snow Leopard (version 10.6) Leopard (version 10.5)	sudo dscacheutil -flushcache
Tiger (version 10.4)	lookupd -flushcache

How to Flush DNS in Windows

Clearing DNS cache is an easy and quick process. The procedure is the same for almost all Windows systems. Foe the example below, we will be using Windows 10.

To flush DNS on your Windows machine:

1. Load the Command Prompt as an administrator. Open the Start Menu and start typing command prompt until you see it in the results.

2. Type ipconfig /flushdns when the prompt loads and hit Enter on the keyboard.

3. The process should take only a few seconds. You should see the DNS Resolver Cache confirmation message when it’s done:

The DNS Cache database on your computer is now clear. You should get the correct and updated IP mapping from DNS servers next time your machine sends a DNS query.

How to Flush DNS Cache in Linux

Linux distributions are a bit different from Windows and Mac machines. Each Linux distribution might use a different DNS service. Some distributions, like Ubuntu, don’t have a default DNS service at all.

It depends on which service you have on your distribution and whether it is enabled by default. Some of them are NCSD (Name Service Caching Daemon), dnsmasq, and BIND (Berkely Internet Name Domain).

For every distribution, you need to launch a terminal window. Press Ctrl+Alt+T on your keyboard and use the corresponding command to clear the DNS cache for the service your Linux system is running.

Flush Local NCSD DNS Cache

Use this command to clear NCSD DNS cache on your Linux machine:

Enter your password if necessary. The process stops and then starts the NCSD service within seconds.

Flush Local dnsmasq DNS Cache

Use this command to clear the dnsmasq DNS cache on your Linux machine:

Enter your password again, if the terminal asks you to. You will see the response when the service stops and starts again.

Flush Local BIND DNS Cache

If you use BIND for DNS service, there are a few commands you can use to flush its DNS cache. You may need to enter your password to finish the process.

Note: BIND also allows you to target specific domains when performing a DNS flush. Just append flushname and the domain name to the sudo rndc command. For example:

You have now learned how to clear or flush DNS cache on macOS, Windows, and Linux systems.

The Internet we use today would not be the same without the immense work that Domain Name Systems do. We, as users, may not be aware of how many processes occur before we see a webpage or receive an email, and that’s why it’s important to flush DNS.

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How to Flush DNS Cache in Mac OS X

Whether you’re a systems administrator or a web developer, or anything in between, chances are you’ll have to flush your DNS cache every once in a while to get things straightened out server-side, or even just for testing certain configurations.

Flushing your DNS cache in Mac OS X is actually really easy, but there are actually several different commands to use, and you will find the commands are unique to different versions of Mac OS X. We’ve got you covered regardless of what version of Mac OS X you’re running, from MacOS Sierra 10.12, 10.11, 10.13, OS X 10.10, OS X 10.9, all the way back to 10.4. So find your version of OS X, open your Terminal, and follow the appropriate directions below to get started.

Remember, each of these commands must be entered into the command line, by way of the Terminal applications (found in /Applications/Utilities/ in all version of Mac OS X). Launch that app first and then you can just copy and paste the commands in if you’d like.

Flushing DNS Cache in MacOS 10.12, 10.11 newer

For Sierra, El Capitan, and newer Mac OS releases:

sudo killall -HUP mDNSResponder

Clearing DNS Cache in OS X 10.10 Yosemite

Running Yosemite? Clearing DNS caches in OS X Yosemite has changed again, split into MDNS and UDNS or combined like we’ll use below, here’s the command that is needed:

sudo discoveryutil mdnsflushcache;sudo discoveryutil udnsflushcaches;say flushed

Flush DNS in OS X 10.9 Mavericks

Rere is how to flush the DNS cache in 10.9:

dscacheutil -flushcache;sudo killall -HUP mDNSResponder

You will need to enter the admin password for this task to complete. If you notice, it combines killing mDNSResponder with the standard dscacheutil, making it a two step process to first, flush cache, then reload the DNS handling in OS X so that the changes take effect.

Flushing DNS Cache in OS X Lion (10.7) and OS X Mountain Lion (10.8)

Launch Terminal and enter the following command, you will need to enter an administrative password:
sudo killall -HUP mDNSResponder
Note the dscacheutil still exists in 10.7 and 10.8, but the official method to clear out DNS caches is through killing mDNSResponder. You can also find that process running in Activity Monitor.

One helpful trick if you find yourself flushing the DNS frequently is to setup an alias for that command string in your .bash_profile or in the profile of your shell of choice. A simple bash alias for flushing cache could be this:

alias flushdns=’dscacheutil -flushcache;sudo killall -HUP mDNSResponder’

Save that into .bash_profile, then typing “flushdns” would prevent having to use the full command string in the future.

Flush DNS Cache in Mac OS X 10.5, Mac OS X 10.6

Launch Terminal and issue the following command:
dscacheutil -flushcache
All done, your DNS has been flushed. On a side note, the dscacheutil is interesting in general and worth taking a look at, try the -statistics flag instead for some stats.

Flush DNS in Mac OS X 10.4 Tiger, & 10.3

Type the following command in the Terminal:
lookupd -flushcache

That’s it, that’s all there is to it. Now your DNS settings should be as you intended them to be, which you can easily verify with various networking tools like http, ping, nslookup, traceroute, curl, or whatever else is appropriate to your specific situation.

If you find something isn’t working and DNS does not appear to have changed, verify the version of OS X you’re running and use the appropriate commands for the latest version. If you’re still having problems after that, try a different machine ideally on a different network (like a cell phone) to verify that it’s not an issue with the remote server.

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Reset Mac DNS Cache in MacOS Monterey, Big Sur On MacOS (Flush DNS Cache)

Last Updated on Jun 26, 2021

flushdns mac with MacOS Monterey is easy with MacOS Monterey on All Macs (iMac, MacBook, MacBook Pro, MacBook Air, Mac Mini). Are you looking to clear and reset the DNS cache in macOS Monterey? Then we have listed some best methods to do so. Periodically users need to reset the DNS cache because sometimes a specific domain or name server is cached or Mac DNS settings have been changed. At that time you need to remove the existing DNS cache. So moving further we will see how to reset the DNS cache in macOS Monterey.

we are happy to help you, submit this Form, if your solution is not covered in this article.

Execute Command in Terminal: Below commands are case sensitive and use space where it needs

How to Flush or Reset DNS Cache in MacOS Monterey On Mac

Step 1: Launch “Terminal” directly from the Home screen using Spotlight. Or “Applications” > “Utilities” > “Terminal.app” or Type “Terminal” in Spotlight search.

Step 2: Now, enter the command below, To execute use your Mac’s system administrator password [Not an Apple ID].

sudo killall -HUP mDNSResponder; sleep 2; echo macOS DNS Cache Reset | say

Step 3: Hit “return key” and then enter the Admin password and again enter.

Step 4: Wait until “DNS cache has been cleared” appears on the terminal screen.

Step 5: Quit “Terminal”.

You must close all the applications running connected to the internet and wait for the changes to take place. Sometimes the changes take place through a simple refresh in the apps.

If in case the above terminal code doesn’t workout for you then you should break that command and write like this,

sudo killall -HUP mDNSResponder && echo macOS DNS Cache Reset

How to clear DNS Cache in MacOS Monterey on Mac

If you have made DNS servers and still you didn’t encounter any changes, then you should clear the DNS cache and again check it this workout for you. It is not necessary to close all the applications which use DNS like Firefox, Safari and other web browsers.

Step 1: Launch “Terminal” from the “Utilities” which you will find in “Applications”.

Step 2: Enter the command with accuracy,

Sudo killall –HUP mDNSResponder;say DNS cache has been flushed

Step 3: Hit return key and enter Admin password.

Step 4: It will take some time to “clear DNS cache”.

Also, you will get a kind of voice message from the system that DNS cache has been flushed.

Alternatively, we have one more command to clear DNS cache if the above one doesn’t work for you,

sudo killall -HUP mDNSResponder;sudo killall mDNSResponderHelper;sudo dscacheutil -flushcache;say MacOS DNS cache has been cleared

How to Reset And Flush DNS Cache in macOS Monterey

Follow the steps to Reset and flush the DNS Cache,

Step 1: Launch “Terminal”.

Step 2: Enter the following command,

sudo killall -HUP mDNSResponder && echo macOS DNS Cache Reset

Step 3: Once you enter the command tap return key and enter the Admin password.

Step 4: It will take few moments to clear cache.

Using Dig to Check Query Times

This method is used to check whether the DNS is perfectly working or not.

Step 1: Open “Terminal”.

Step 2: Type “dig howtoisolve.com”. In place of our website, you can enter any website to check query time.

Step 3: You can check result in “Query Time”.If query time is more then change macOS DNS settings to Google DNS.

After changing the DNS server to Google DNS, you can verify the query time again by the same dig command.

Hope you get pro tips, why you shouldn’t share this helpful guide with others. Share this page on your profile and recommend to your friends for more tips and guide on MacOS Monterey issues and problems.

jaysukh patel

Jaysukh Patel is the founder of howtoisolve. Also self Professional Developer, Techno lover mainly for iPhone, iPad, iPod Touch and iOS, Jaysukh is one of responsible person in his family. Contact On: [email protected] [OR] [email protected]

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