DNS Explained | Domain Name System | Cisco CCNA 200-301

Join the Discord Server!
/ discord
---------------------
MY FULL CCNA COURSE
📹 CCNA - certbros.teachable.com/p/cisc...
FREE CCNA FLASHCARDS
🃏 CCNA Flashcards - certbros.com/ccna/flashcards
HOW TO PASS THE CCNA
📚 Get a great book - amzn.to/3f16QA5
📹 Take a video course - certbros.teachable.com/p/cisc...
✔ Use practice exams - www.certbros.com/ccna/Exsim
SOCIAL
🐦 Twitter - / certbros
📸 Instagram - / certbros
👔 LinkedIn - / certbros
💬 Discord - www.certbros.com/discord
Disclaimer: These are affiliate links. If you purchase using these links, I'll receive a small commission at no extra charge to you.
---------------------------------------------------------------------------------------------------------------
The Domain Name System (DNS) plays a very important role in modern-day networking. It's an unsung hero that allows us to use the internet in the simplest way possible. Without DNS, our connected lives would look very different.
DNS will take our domain name, and translate, or resolve it, into an IP address.
Let's say you want to go to your favourite website, so you type, www.certbros.com.
Remember, web servers do not work with domain names, so your computer needs to translate this into an IP address.
The first thing it does is check its local cache both on the computer and the browser. There’s also a local configuration file that's checked.
If there are no cache entries, your computer will send a query to something called a DNS recursive resolver asking for the IP address of certbros.com.
Once the DNS resolver receives your query, it checks its cache. If it can’t find an entry for certbros.com, it will send a request to another server, this is called a ROOT server.
The root server will then refer us to the top-level domain server (TLD) for .com. A TLD server is a server that contains information for domains with a specific extension. For example .com .org .net etc
The TLD server will then refer us to the authoritative nameserver.
The authoritative nameservers will have a record for Certbros.com and it will return the IP address to our DNS Resolver which will then send it back to our computer.
Out computer will now be able to contact the webserver using the newly discovered IP address.
#ccna #cisco #networking

[@Nay-fm9sl]

a visual learner appreciates you!

[@Certbros]

I'm exactly the same! This is the reason this channel exists 👌

[@anonymousfan9703]

​@Certbros Being the small minded humans that we are 😂😂😂😂😂 Best line

[@anup_narvekar]

I've checked 10+ videos from popular sources on DNS resolution, everyone has a variation of their own while explaining DNS lookup, leaving me in confusion. They can spend hours in making those attractive animations, but can't afford to spend time in researching on how to actually demonstrate the DNS resolution process. You made the entire process very clear with a practical demo, so really thanks for that! Respect++ for your knowledge and research. My research on DNS resoluting ends here!

[@53Karter]

Just watched most of these videos this morning. I learned and retained more information here than I have in my Internet class at University. Thank you

[@itaybarok9405]

Your using of wireshark and clear images are highly useful. I learned the root, TLD and Authoritative that are hiden in the process of giving the ip of a url so that we can use it the reach the server. Also I saw that dns uses cache which is really effective. I also saw the type A of IPv4 and type AAAA of IPv6 in wireshark.

[@taydorion6467]

I swear I appreciate you guys so much I needed this break down !!! 🙌🏽

[@AnasMations]

I've checked 3 sources trying to understand DNS but yours was the most clear and straight to the point explanation. Thanks!

[@guyot1979]

Just found CertBros. Glad I did! Im here to echo all the other positive comments. Well done! I especially appreciate the bite size chunks, Easily digested, and easy to go back and review. Dense 90 minute videos are too much to take in. Thanks!

[@Certbros]

Thank you Gregory! Really great to hear you like the videos! Easy to watch and understand is exactly im aiming for.

[@charlesluhmann]

Incredible video. The best I've seen on explaining the basics of DNS.

[@cammycool1627]

3:37 - Top level domain server or TLD ;-) Thanks so much for these, big bro! You're a legend! Coolest IT videos in internetz!

[@Certbros]

Damn! I didn't think it would be that noticeable. Haha! Thanks man, really appreciate it! 👌

[@bossvoip]

Awesome! Very well explained and I like the wireshark bit as well

[@adriennewilson1680]

New subscriber here! I love ur videos & there simple to understand. I just can’t watch a 60 minute video 😭 I need short & to the point and you’ve mastered that so Thk u!!

[@divyanshuverma3205]

Love you bro ... Stay blessed and happy 🎊 Keep up the great work !!!!

[@omarebadah2238]

The most facilated explanation! Thank you Man!

[@tubadurantdoda]

Thank you Certbros for being so awesome!

[@tresmcneil]

Awesome tutorials thanks. How do non TLDs differ from the basic TLDS? I see a lot more of those lately.

[@ardentdfender4116]

Another awesomely explained vid. A few more vids studying early at 3AM in the morning and I be done with your complete CCNA List. Will go thru it again entirely Sunday Night as a last speed review before my Exam on Monday Morning. I’m wondering though, how or where do you learn all those Windows PS networking commands? I’m only familiar with a short few commands like ipconfig, ipconfig /all, tracert barely a handful. But where do you find a good list of useful commands?

[@davidbell7094]

Mind blown but extremely interesting. Thank you 👌

[@rogerthat7190]

Awesome video!!

[@muhammadraza7231]

Oh my goooddd. He is master in explanations😍 I subscribed

[@Certbros]

Haha! Thank you Muhammad! Great to hear you enjoyed the video 👍

[@Don-Carillo]

Just brilliant. As always

[@Certbros]

Gracias Don Neto!

[@jamesgriffin7734]

Wow this video was amazing. You guys are great very easy to follow

[@Certbros]

Thanks James, appreciate it!

[@habtamusium8646]

what understandable methodologist r u ? u did clear my mind , i must subscribe to learn more esp networking, i am in love wz system and spend time everyday to know about. much thanks !

[@mdnaseer6378]

Love your content!

[@jordanweir7187]

Amazing content, very instructive

[@shafeen1058]

Thank you for breaking down the dns

[@zeenaal-aldawoody2208]

Thank you ❤

[@maknetworks7229]

GOAT as always

[@dencam]

Thanks for sharing this. I have just booked for my CCNA exam in 2 weeks.

[@Certbros]

Good luck Dennis! You are going to smash it! 👍 Let us know how it goes.

[@alexmilliken1518]

did you pass the exam?

[@dencam]

@@alexmilliken1518 Yes I passed with a score of 930/825

[@alexmilliken1518]

@@dencam heyo good job

[@ndedivine5068]

Well articulated Sir. Thanks

[@abhishekaouchat8419]

Sir! you just nailed it. Awesome detailed explanation specifically steps after Root DNS resolver. I subscribed. There is one this I wanted to point out regarding TLD and you kept saying TDL. Just as a curiosity can we say it as TDL?

[@Certbros]

Thank you Abhishek! Welcome to the channel 👌🎉 Great spot! This was a mistake. It should always be TLD.

[@noodler911]

@@Certbros You are really amazing mate! You have my respect!

[@elmehdibenseddik2689]

Great Tutor and interesting video contents... Thank you to keep posting

[@Certbros]

Thank you! Glad you liked the video.

[@jhde9067]

Do you have a video on how to create a DNS resolver server? You seem to have very good content, I'm considering subscribing.

[@seetsamolapo5600]

-DNS resolver usually run by your ISP but can be run internally

[@Spaniards56]

Thank you again for your info!

[@Certbros]

My pleasure Flavio!

[@user-hx1es3li8p]

Thank you for this videos

[@cyriljohns]

Thank you very much

[@storaman12]

THANK YOU.

[@upalidharmasiri155]

Excellent Teaching !

[@Certbros]

Thank you!

[@gerardklien6889]

This is awesome

[@aruizsilva]

than you very much!

[@LightBueno]

Thanks alot 👍

[@lsontech237]

Thank you

[@wmblasius3794]

One thing I would have liked to see is an explanation of how DNS handles DHCP assigning a new IP address to an old URL.

[@Certbros]

Great suggestion. Thanks for the feedback 👌

[@Amphibiot]

"It's DNS" "It's not DNS" "It was DNS" "It's always DNS"

[@thefreedom111]

Very informative👍

[@Certbros]

Thank you Daniel!

[@JoseGarcia-uz8uc]

Thank you!

[@Certbros]

You're welcome Jose!

[@JamesSmith-cm7sg]

Excellent video, thank you. How does DNS determine the closest server for distributed systems?

[@Certbros]

Thanks James! Really appreciate it 👍 Anycast DNS is an option for location-based DNS.

[@NachoManBoy4]

@certbros -- at the 4:42 mark your narrator referred to a TDL. As I have taken notes and studied your content so far, I am unable to resolve TDL to a term I have learned. I am currently stuck at this point in the video because I must learn TDL before moving on, in case it is important. Thank you.

[@Certbros]

Sorry Ryan, this was a mistake. I was supposed to say TLD not TDL.

[@NachoManBoy4]

@@Certbros Understood now, thank you sir.

[@annm.8231]

@@Certbros Thank you! Watching this video now and I was getting confused. Thanks for the clarification.

[@SolucionesELP]

Very good videos thanks a lot , may I ask you what software you use for making animation?

[@Certbros]

Thank you! I use After Effects and Premiere Pro. Links are in the description if you want to check them out. 👍

[@SolucionesELP]

@@Certbros thanks a lot

[@WeBBerTutoriais]

Great!!!

[@Certbros]

Thank you 👍

[@arjunmadhav94]

Can you please do a video on BGP ? 👍 Thanks !!!

[@Certbros]

Definitely 💯

[@anthonyisensee]

2:45, love the LOL @ Yahoo.com. :D

[@vauxhallchevette5858]

Just keep uploading these videos.

[@Certbros]

Thank you!

[@MOMO-YYDS]

❤😊

[@alifarooq77]

First😎

[@Certbros]

Legend! 👌

[@rafay1708]

nice

[@Certbros]

Thanks

[@mcpulya6890710]

Why do we need the root for and not just go stright to TLD?

[@lakatosalex]

3:37 T L D, not tdl, must be a typo/speech-o?

[@Certbros]

Great spot. I kept saying TDL. I also say it at 4:41 🤦‍♂️

[@andywarrier489]

So why did we use UDP to send the info and not TCP

[@justcurious1940]

Is to much for a root servers to resolve all existing Domain names instead of this long journey to get this 4 bytes information ?

[@sartoriusrock]

One thing I have never quite understood is why there must be 4 different DNS servers. Do each hold different levels/amounts/classes of addresses in their DNS caches?

[@sartoriusrock]

And, if the Resolver, Root, or TLD does have it in the cache, does it shortcut the need to contact the servers "higher up the chain"?

[@reprisal1051]

Yea it’s super effing confusing

[@sasansaljoughi1893]

thank god ! a great explanation without a terrible Indian accent

[@georgetsiklauri]

3:35 TLD, not TDL. :)

[@mobamba914]

you said TDL again at 4:45 lol

[@nigelang5985]

TDL? or TLD?

[@bakyhummedow373]

cool bros

[@Certbros]

Thanks!

[@rohansharma4844]

Where is the full course ? i opened the link and it said it is under work ?

[@yofi2614]

I don't get it! why not go directly to the name server in the first place?

[@a-face9333]

do you even cert bro?

[@RosiePaintsMinis]

i swear you also make skyrim videos

[@whpromo]

Why does the narrator keep referring verbally to the TLD server as the TDL server??

[@themistoclesnelson2163]

Any update on the full course?

[@Certbros]

Still working on the content. I'm just about to release some new videos in the next few days. Then I'll be starting on the practical labs. Have you already signed up?

[@themistoclesnelson2163]

@@Certbros Oh cool! Yes I have! Scheduled my exam for December.

[@Certbros]

@@themistoclesnelson2163 Great to hear it! Keep up the studying and you'll smash the exam 😁 Feel free to email me anytime.

[@themistoclesnelson2163]

@@Certbros Thanks! Thats why your the man!

[@Spankytimez]

Yahoo (LOL)

[@JK-cp9pt]

Yahoo(lol) 🤣🤣🤣🤣

[@Certbros]

😂

[@youmich]

tld, not tdl

[@Certbros]

Good spot!

[@user-sx7wt6ny3d]

ביאששששששששששששששששששששש

[@Channel-qr5mh]

What is the IP of Root DNS server? DNS Explained doesn't seem well explained.

[@the77th]

Can I donate

[@Certbros]

The only donation I need is a like and a subscribe! 😁 But if that really isn't enough, you can check out my CCNA course here: certbros.teachable.com/p/cisco-ccna/?product_id=2833094&coupon_code=PRELAUNCH21 Glad you liked the videos.

[@the77th]

@@Certbros just purchased ❤️❤️❤️❤️! Will this course help me study and pass the ccna 200-301 ?

[@Certbros]

Thata great to hear. Thank you 🙏 Yes this course will absolutely help you pass the CCNA. Good luck with your studies and enjoy the course 👌

[@user-rb8bl3gs9k]

You have it as TLD but are saying TDL.. just a heads up friend! Thanks for the explanation in the video! 😁

[@strcelrau]

ti-di-el?

[@Certbros]

TLD*

[@thesootsplays1975]

Nice content- please change your intro.

[@Certbros]

Thank you. Out of curiosity, what about the intro don't you like?

[@BeachSamuraiStudios]

@3:50 TLD not TDL

[@modapothularajasekhar4645]

Thank you

[@gansgross6464]

Thank you

[@Certbros]

You're welcome