Name: DNS中的A記錄 - 什麼是... (A Records in DNS - What are...)
Uploaded: 2021-01-14T10:18:42.000Z
Duration: 5 min 13 s
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So the question is, is what is an A record in D.

N s configurations, once you buy a domain name such as failed normal dot com or geek field notes dot com, you'll see there's a whole bunch of different settings you can put in there.

And so let's talk about what a record is.

What a record does is it allows you to point a sub domain to a particular I p address.

It only allows you to point to an I P address.

You can point to 10.1 dot tender 11 only to 11 68.1 dot one or, you know, some kind of Internet addressable address.

Basically, you're able to put an I P address with the A record, and so what you can then do is you can have www point to whatever this specific I P address of your server is.

Here you can not put domain names in here.

You can't put ah mail dot google dot com and here or anything like that.

What this does is this Maps sub domains to I p addresses specifically nowthe one configuration that you may have to put in there with most of these D.

So this will be the default, a record, and basically what this state's is.

Where is your default server at so four default?

So if you go in normally, whenever you set up the domain names with some place, like go down to your host gator, this'll be pre configured.

Basically, what you do is you create in a record, you use the at symbol, and then you point the at symbol at whatever I P address there is for your server.

And so this is why, even if you don't use a sub domain most of time, you can still get to somebody's Web server.

So if you go to www dot fail normal dot com, that will obviously drop you on the Web server because you're using the sub domain.

But The question is, is what happens if you simply put in failed normal dot com without the W W.

Without in a sub domain in front of that?

And so that's where this initial at a record will point.

You know when somebody just plugs in the domain name without anything else.

And so this is where you can make mistakes.

Sometimes people aren't thinking about it.

They'll change where www points, too, but they'll forget to change that at a record.

And so if somebody puts in www dot fail normal dot com, they'll go to the appropriate website.

But if they just plug in failed normal dot com.

If you hadn't haven't came that configuration, they'll continue to go to wherever your your site was set up before, and they'll most likely get bounced out of it.

So as far as using W W W as in a record generally standard practices you don't use WWW in your a record.

What you dio is you created a record for the at symbol on pointed toe What it wherever I go.

Whatever I p address your Web server is that then What you do is you go into the sea.

Name records of sea name allows you to plug in domain names versus I P addresses on See names.

You can point a sub domain at a at another domain name, but you can't plug in an I p address.

They'll create a C name Www, and then they will point that at the at symbol.

So the at kind of comes becomes like a wild card.

So once you plug the at symbol into your initial a record than anywhere else, you can just plug the at symbol in within the sea names, and then it will default.

Tow whatever you plugged into that a record.

So what happens is a lot of times, you know, a lot of servers they'll provide multiple service is.

So when you're creating your see names, www will point to the act.

Then let's say your mail service is that will point to a domain name.

So, for that's a male, you know, Google's mail service or Microsoft Mail Service.

But then the FTP that may then point to the ad because your your Web server and your FTP server, maybe at the same place.

Additionally, maybe you're VPN servers and then VPN dot and that would just get pointed toothy at.

So it's very important to understand, with a record, the A record points sub domains to I p addresses now, theoretically, theoretically, yes, you could.

Within the A record, do Www and point that an ad an I P address.

But the standard procedure is is what you do is you created a record for the at simple You point that at the I P address for whatever your Web server is than under the sea names at sea names, you add a W W W.

And then you point that at the at, assemble again acts like a wild card, and that's a way to keep it very easy for administration.

 For when administrators after you come in and they're trying to figure out what's going on, that's kind of the standard operating procedure, so that's what a records are, and that's why you should care about them. 