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Hey guys and welcome back. So in the previous nugget we had looked at some tools that we

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could use to make particular DNS requests, those were their forward lookups as well as

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reverse lookups. Now in the output of those tools we happen to see references to particular

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records. So like I say the very first record is that A record and when we have an A record

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what we're talking about is that this record is actually going to have IPv4 information

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about a particular domain. So if you happen to have a particular domain such as maybe

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say cloudflare.com and that might point to an IP address of let's say 1.1.1.1 this would

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be an IPv4 address therefore that information is going to be stored in the DNS A record.

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Okay now the next one is not relating to IPv4 you can probably guess the next one I'm going

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to talk about is relating to IPv6. So this is what is called an AAAA record or a quadrature

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record I've heard also be called or a quadruple A if you prefer. Now this is going to be the

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same type of information relating to an A record but like I say inside it we're going to see that

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hexadecimal IPv6 addressing. So that really is the only difference we're going to see here with

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respect to our A record and our quadruple A record. The next record I just want to briefly

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mention to you is one called the CNAME record. Now this record is all about passing information

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between particular domains now crucially this doesn't actually relate to IP addressing information

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this is about the domain names themselves in fact I should actually add that this can also relate to

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sub domains to okay which like we talked about before that could be like drive.google.com that

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information being passed around will be related to the CNAME record. Now recall in the previous

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nugget we happened to use the reverse lookup so we could say host for a particular IP address

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and we could see that we get information relating to a particular domain. The actual information

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here that we are drawing from is what is called the pointer record this is something I've referred

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to oh get my drawing pen on the go this is something referred as the PTR record otherwise

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known as pointer. This can be thought of as like the mirror opposite the inverse mapping of the A

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record like I say the A record is going to give you the IP address from the domain name the pointer

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record is going to give you the domain name when you supply an IP address. Now the reality is there

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are a ton more DNS records available we can have things such as an MX record this happens to relate

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to mail servers you may recall that when we happened to use I believe it was the host command

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say for example I did host google.com but also getting information relating to the mail we can

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actually derive this information from that MX record and like I say there are even more records

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such as the SOA record this is going to store administrative information about a particular

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domain we can also have a TXT record these allow you to store text data within a particular record

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and we can also have the SRV record which will allow you to actually detail particular information

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relating to ports on a particular service so like I say we have a whole bunch of different records

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and the reality is for the purposes of the examination you do not have to be too worried or

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aware of all of the deep details of all of these records but if you happen to be deploying some

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DNS server for real and the real world of course you do want to be aware of what these different

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records are how they can be implemented what they actually do so definitely I would advise

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for the real world having a good grasp of these different records is going to make your life

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much much easier but for now what I want to do is to move on and actually get hands on with respect

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to our DNS server configuration and well that's what we're going to be talking about in the very

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next nuggets I hope this has been informative for you and I'd like to thank you for viewing