Getting Started with Domain Name System (DNS) | Network Fundamentals Part 17

Getting Started with Domain Name System (DNS) | Network Fundamentals Part 17
The Domain Name System (DNS) is the elegant system used for, among other things, resolving a name to an IP address.

Think about when you put a web address into a web browser. That needs to be converted to an IP address, so the client will send the DNS server a lookup message, and the DNS server will send a response.

DNS servers contain zones, which is a container for all the information for a domain. If a DNS server has a zone for a domain, it is authoritative for that domain. If it is non-authoritative, it can make its own query, and send it to another DNS server.

Inside the zone are records. These contain the information such as name to IP mappings. This particular type is called a host or ‘A’ record. Other types include a pointer (PTR), which is the reverse of the host record, the canonical name (CNAME), which is an alias, and the Mail Exchange (MX) record, which holds a list of mail servers.

When a server can’t answer a request on its own, it needs to ask another DNS server for help. One option is to configure another server as a forwarder. The server performs a recursive query, where it finds a record on the client’s behalf.

The alternative is to use root hints, where the server asks other servers for hints about where the authoritative DNS server is located. It does this using recursive queries

Overview of this video:

0:00 Introduction

0:36 The Domain Name Space

2:10 Zones and Records

4:32 Record Types

6:10 A Simple Lookup Process

9:31 Using Forwarders

10:58 Using Root Hints

12:58 Quiz

LET'S CONNECT

#NetworkDirection

[georgestavroulakis]

Every single video so far, is an amazing job! Thanks for your great work!

[haleemtemitope]

This is one of the best Network Tutor resource I have come across, kudos!

[ali_HA]

As always amazingly simplified explanation. Love your videos !!!

[jpick]

wow I've read a lot about and never found such a perfect and easy explanation. Good job!

[uzoruchenna]

This is amazing. Far better than google networking course on coursera

[abulaith]

Thank you for this great intruduction. Will be great if you can make another more advanced content on DNS!

[WineTwoThree]

Excellent explanation. Thank you for your effort.

[satishkumar-rtps]

why am i so late on this channel :(, just wow!!
you earned a subscriber

[medilies]

I have probabilities exam tomorrow. But I have to stop preparing and watch this lol.

[MsPgouru]

@Network Direction Using root hints and find the IP address is an iterative query per video? But video description/summary says recursive? Or Am I missing something?

The alternative is to use root hints, where the server asks other servers for hints about where the authoritative DNS server is located. It does this using recursive queries

[quetzaltorz]

Why don, t you allow community contributions to subtitle it? These videos are amazing, but not everybody understands English, and I could help to translate them into Spanish.

[pisco]

Hi, great tutorials!
I have a question: at 12:33, why is it looking for the answer in a ".COM" DNS server if the domain it's ultimately looking for is a ".NET" domain ?

[sharmiladevi]

Do we have link for dns configuration in linux .. ?