浏览器dns查找失败

So, for those of us who work, play, and communicate over the Internet, we all hear the term “DNS” at least occasionally, if not often. DNS is an acronym that stands for “Domain Name System”. DNS is the cornerstone of the Internet - it is how we navigate from site to site.

因此，对于我们这些在Internet上工作，娱乐和交流的人，我们至少偶尔（即使不是很经常）都听到“ DNS”一词。 DNS是首字母缩写词，代表“域名系统”。 DNS是Internet的基石-这是我们在站点之间导航的方式。

DNS解析 ( DNS Resolution )

So, when I type www.example.com into my browser window (I happen to use Chrome) and hit enter, it magically loads a website, right? No? OK. So it turns out that the process of acquiring the IP address that we need in order to actually load a website is a long and somewhat convoluted one. Let’s take a look.

因此，当我在浏览器窗口中输入www.example.com （我刚好使用Chrome）并按Enter时，它会神奇地加载网站，对吗？ 没有？ 好。 因此，事实证明，获取我们实际加载网站所需的IP地址的过程是一个漫长而复杂的过程。 让我们来看看。

IP地址 (IP Addresses)

So first, how does one even locate a computer or server on the Internet? A hosting server, just like any other computer that's connected to the Internet, has what is called an “IP Address”. An IP address (using the current addressing system, called "IPv4 ") is a sequence of four sets of numbers separated by dots such as 111.222.333.444. The address is completely unique to that computer - none other on the Internet should have the same address. Unlike our home Internet connections, which sometimes change to new IP addresses when our equipment is restarted, or after a certain length of time, IP addresses of web servers are usually “static” - they never change. In short, the IP address is a unique set of numbers that allow the computer to be found among all of the other devices connected to the Internet.

因此，首先，人们如何在Internet上定位计算机或服务器？ 与连接到Internet的任何其他计算机一样，托管服务器也具有所谓的“ IP地址”。 IP地址（使用当前的寻址系统，称为“ IPv4”）是由点（例如111.222.333.444分隔的四组数字的序列。 该地址对于该计算机是完全唯一的-Internet上的其他地址都不应具有相同的地址。 与我们的家庭Internet连接不同，有时在重新启动设备时或经过一定时间后会更改为新的IP地址，而Web服务器的IP地址通常是“静态”的-它们永远不会改变。 简而言之，IP地址是一组唯一的数字，可以在连接到Internet的所有其他设备中找到该计算机。

本地缓存 (Local Caches)

Awesome, back to our attempt to retrieve and load a website. The first thing that happens when we type in the domain name that you wish to visit into your browser window is a check of your browser’s local cache. If your browser has already been to this website recently, it may already know what the IP address for the website in question is, and have that value cached. Browser caches don't usually last long, so it would've been a recent visit. If it doesn't have the information in its cache, it will then also check our computer's DNS cache. This operates in much the same way - if the computer has been used to visit the website recently, it saves the IP address for as long as it has been instructed to do so - this is the "Time to Live" setting, which we'll come back to later.

太棒了，回到我们尝试检索和加载网站的尝试。 当我们在浏览器窗口中输入您想访问的域名时，发生的第一件事就是检查浏览器的本地缓存。 如果您的浏览器最近已经访问过该网站，则它可能已经知道该网站的IP地址是什么，并已将该值进行了缓存 。 浏览器缓存通常不会持续很长时间，因此这是最近一次访问。 如果它的缓存中没有信息，它还将检查我们计算机的DNS缓存。 此操作的方式几乎相同-如果最近使用计算机访问了该网站，则只要保存了指示，它就会保存IP地址-这是“生存时间”设置，我会回到后面。

If either of our local caches, the one in our browser or the one the computer retains, already had the IP address of our website stored, then we’ve already reached the end of the first part of the process of loading our website - we've acquired the IP address. Part two, of course, is then sending a request to that IP address in order to actually load the website in question! This all happens in milliseconds, unbeknownst to us, the users, and we continue browsing. End of story!

如果我们的本地缓存，浏览器中的缓存或计算机保留的本地缓存中的任何一个已经存储了我们网站的IP地址，那么我们已经到了加载网站过程的第一部分的结尾-已获取IP地址。 然后，第二部分当然是向该IP地址发送请求，以实际加载有问题的网站！ 所有这一切都以毫秒为单位，对于我们，用户来说是未知的，并且我们继续浏览。 故事结局！

递归DNS服务器 (Recursive DNS Servers)

If, though, our browser can't find the IP address that it is looking for locally, it has to reach out and contact its recursive DNS server.

但是，如果我们的浏览器找不到本地要查找的IP地址，则必须伸出手并联系其递归DNS服务器。

“Recursive DNS servers” is a mouthful; what does that mean? These are most often one or more DNS servers which are located at our Internet Service Provider, or ISP (the company that is selling us Internet service). Our ISP automatically assigns us their default DNS servers while we are on our Internet connection. We never even have to know or care about it! Some users change these settings, which we'll talk more about in the details section later in the article.

“递归DNS服务器”令人mouth目结舌； 那是什么意思？ 这些通常是一台或多台位于我们的Internet服务提供商或ISP（向我们出售Internet服务的公司）上的DNS服务器。 当我们处于Internet连接状态时，我们的ISP会自动为我们分配其默认DNS服务器。 我们甚至不必知道或关心它！ 一些用户更改了这些设置，我们将在本文后面的“详细信息”部分中详细讨论这些设置。

When our system is not capable of finding the DNS records for the domain that it seeks in its local cache, it next checks with the recursive DNS servers. If those servers already have the IP address we’re looking for in their cache (which would mean that someone else - another customer, probably - using these DNS servers has visited this site recently, and the information got saved there for later use, which is handy for us right now) then we're done! The information is returned to our operating system and then our browser, and we send our request to that IP address to load the website, and off we go.

当我们的系统无法在本地缓存中查找该域的DNS记录时，接下来将检查递归DNS服务器。 如果这些服务器已经具有我们要在其缓存中查找的IP地址（这意味着使用这些DNS服务器的其他人-可能是另一位客户-最近访问了此站点，并且该信息已保存在那里供以后使用），现在对我们很方便），那么我们就完成了！ 信息先返回到我们的操作系统，然后再返回到浏览器，然后我们将请求发送到该IP地址以加载网站，然后我们就离开了。

根DNS服务器 (Root DNS Servers)

If the recursive servers didn’t have have the records we are looking for in their cache, then what is next? Our request is about to get bounced around a variety of computers (servers) so that it can get to a server that can tell it what we want to know. So, hang on.

如果递归服务器在缓存中没有我们要查找的记录，那么下一步是什么？ 我们的请求即将在各种各样的计算机（服务器）上反弹，以便可以到达可以告诉我们我们想知道什么的服务器。 所以，等一下

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First, our request now travels to what are called the “root name servers”. The root name servers serve as a type of gatekeeper, controlling access to the next layer of DNS servers. All they do is locate an appropriate server for our request to go to next. The root name servers are dispersed around the world, and controlled by several separate organizations. The reason for this is to ensure that they won’t all be taken out of commission by a single disaster or failure!

首先，我们的请求现在传递到所谓的“根名称服务器”。 根名称服务器充当一种网守，控制对下一层DNS服务器的访问。 他们所做的只是为我们的请求找到合适的服务器。 根名称服务器分散在世界各地，并由几个独立的组织控制。 这样做的原因是为了确保不会因为一次灾难或故障而将它们全部淘汰！

The root name servers redirect our request to the name servers for our requested top-level domain (TLD).

根名称服务器将我们的请求重定向到我们请求的顶级域（TLD）的名称服务器。

顶级DNS服务器 (Top Level DNS Servers)

Each domain ending like .com or .org has its own name servers that can help us out. We'll have been passed off to one of those by the root DNS servers, and they can help us out because they know the location of the "golden ticket" - they know where the server is that is holding the information we seek! They will pass our request on to the next, final step in line - the Authoritative DNS Servers for our domain.

每个以.com或.org结尾的域名都有其自己的域名服务器，可以为我们提供帮助。 我们将由根DNS服务器传递给其中一个服务器，它们可以为我们提供帮助，因为他们知道“金牌”的位置-他们知道服务器在哪里保存着我们寻找的信息！ 他们会将我们的请求传递到下一步的最后一步-我们域的权威DNS服务器。

There used to be only a handful of top-level domains (TLD) like .com and .org and .net but now there are many, many more like .online and .rocks and .careers. Every TLD has its own name servers that can help us out. That is why we needed the Root DNS Servers above - there are so many domain extensions, with more being added all the time, our poor computer would have no idea how to find out about them. So the Root DNS server can tell us where our extension's servers are, and then we head here to find out where to go next. In our case, if we are trying to find www.example.com, the .com name servers will be the ones we need to direct us to the next step. The .com name servers will now tell us where to find the authoritative name servers for our specific domain.

过去只有少数顶级域名（TLD），例如.com和.org和.net但是现在还有更多很多.online ， .rocks和.careers 。 每个TLD都有自己的名称服务器，可以为我们提供帮助。 这就是为什么我们需要上面的Root DNS Servers的原因-域名扩展太多了，而且一直在添加更多的域名扩展，我们可怜的计算机根本不知道如何查找它们。 因此，根DNS服务器可以告诉我们扩展程序的服务器在哪里，然后我们前往此处查找下一步。 在我们的案例中，如果我们试图找到www.example.com ，那么.com名称服务器将是我们需要将其引导到下一步的服务器。 .com域名服务器现在将告诉我们在哪里可以找到我们特定域的权威名称服务器 。

权威DNS服务器 (Authoritative DNS Servers)

The domain name’s authoritative name servers are the place responsible for delivering information about our domain to the rest of the Internet. The chase ends here.

域名的权威名称服务器是负责将有关我们的域的信息传递到Internet其余部分的位置。 追赶到此结束。

When you first register your domain, your registrar often provides this service for you automatically. They've got a set of servers which will be responsible for keeping track of your DNS records, and providing those records to any requests that come their way - like the one we are making right now. If you set up hosting for your website, the host may ask you to instead switch over and use their name servers for this task, which you will then continue to do as long as you're hosting your site with them. Most often, this is the only time you would change your authoritative DNS servers - when selecting, or switching, hosting providers or domain registrars.

首次注册域名时，注册商通常会自动为您提供此服务。 他们有一组服务器，这些服务器将负责跟踪您的DNS记录，并将这些记录提供给按其方式进行的任何请求-就像我们现在正在进行的请求一样。 如果您为网站设置托管服务，则托管服务商可能会要求您切换并使用其名称服务器来执行此任务，只要与它们托管网站，您就可以继续执行。 通常，这是唯一一次更改权威DNS服务器的时间-在选择或切换托管提供商或域注册商时。

In any case, now we are here, at the authoritative DNS servers, and we ask them for the A Record for the domain that we typed in. It delivers us the record, which consists of an IP address for the server our website is hosted on. This is what we've been looking for! This information, in most cases, is then cached (stored for later use) by our recursive DNS service that we talked about earlier, and then also cached by our own computer. These caching steps will make a return trip to this website a bit shorter - sometimes imperceptibly, but sometimes a noticeable amount.

无论如何，现在我们都在权威的DNS服务器上，并要求他们提供键入的域的A Record 。它为我们提供了记录，其中包括网站托管服务器的IP地址上。 这就是我们一直在寻找的！ 在大多数情况下，此信息然后由我们之前讨论的递归DNS服务进行缓存（存储以供以后使用），然后也由我们自己的计算机进行缓存。 这些缓存步骤将使回程到此网站的时间略短-有时会察觉不到，但有时却很明显。

结果 ( Results )

OK! We’re done, and our website is now loading (unless the website itself has errors, or the hosting service, but let’s leave that for another day, shall we?). So, let’s do a quick overview of what the process was:

好！ 我们已经完成了，我们的网站现在正在加载（除非网站本身有错误或托管服务，但是让我们再待一天，对吗？）。 因此，让我们快速概述一下该过程：

• We type in a domain name (www.example.com) into our browser.我们在浏览器中输入域名（ www.example.com ）。
• The browser checks its cache and the computer's cache for the DNS records for that match the domain name we entered. If it succeeds, it requests the page from the website's host.浏览器检查其缓存和计算机缓存中是否有与我们输入的域名匹配的DNS记录。 如果成功，它将从网站的主机请求页面。
• If we haven’t found our record yet, our request goes to our Recursive DNS Servers that we have set for our computer or network (probably our ISP). If they have the record cached, we take the results from them and try to load the page (and we also cache it locally for later use).如果我们尚未找到记录，我们的请求将转到为计算机或网络（可能是ISP）设置的递归DNS服务器。 如果他们缓存了记录，我们将从它们中获取结果，并尝试加载页面（我们还将其缓存在本地以供以后使用）。
• If we still haven’t found it, we go to the Root DNS Servers, and ask them where to find the correct Top Level DNS Servers for the .com TLD. 如果仍然找不到它，请转到根DNS服务器，并询问它们在哪里为.com TLD找到正确的顶级DNS服务器。
• We arrive at the .com Top Level DNS Servers, who have one nugget of information for us - they are kept up to date on which Authoritative Name Servers are responsible for example.com and they share that information with us.我们到达了.com顶级DNS服务器，它们为我们提供了一系列信息-它们保持最新状态，权威名称服务器负责example.com并与我们共享该信息。
• Then, we head over to the Authoritative Name Servers, who give us the record we’re looking for.然后，我们转到权威名称服务器，它们为我们提供了我们想要的记录。
• Finally, the result is cached by the recursive DNS servers, and by our local system - and we load our page!最后，结果由递归DNS服务器和我们的本地系统缓存-我们加载了页面！

设置DNS记录 ( Setting Up DNS Records )

So now that we know how the DNS request process works, what about setting up DNS records for your own domains? DNS Records are a set of information, primarily IP addresses. These records indicate various things about our domain - where to go when we type in the domain name (example.com), or www.example.com, where to go when other subdomains (employees.example.com) are used, and how to handle email for our domain, among other things.

因此，既然我们知道DNS请求过程的工作原理，那么为自己的域设置DNS记录又如何呢？ DNS记录是一组信息，主要是IP地址。 这些记录表明有关我们域名的各种信息-键入域名（ example.com ）或www.example.com时要去哪里，使用其他子域（ employees.example.com ）时要去哪里。处理我们域的电子邮件等。

We edit these records, usually, on our domain registrar or our website host's control panels. The records themselves live on the above mentioned "Authoritative Name Servers", and are primarily made up of locations (IP addresses and domain names) and time to live numbers (discussed more below). Some direct people to our website, some direct them to subdomains, or different areas of the site, or different related sites. Some exist for the direction of email, and some for other purposes altogether. Let's dig in a bit and take a look at a few.

我们通常在域注册商或网站托管人的控制面板上编辑这些记录。 记录本身位于上面提到的“权威名称服务器”上，并且主要由位置（IP地址和域名）和生存时间（下面将详细讨论）组成。 有些人将人们定向到我们的网站，有些人将他们定向到子域，站点的不同区域或不同的相关站点。 存在一些用于发送电子邮件的方向，而某些则用于其他目的。 让我们深入研究一下。

There are two big components we see in DNS records - hostnames and time to live numbers.

我们在DNS记录中看到两个主要部分-主机名和有效时间。

主机名 (Hostnames)

Hostnames, in this context, are really just referring to the specific place you're wanting to go. With our illustration, if there was a site called example.com, being entered without any www. or anything else in front of it, we would use the symbol @, when editing a domain record, to indicate that we're referring to the "naked domain" - without anything prefixed ot it. We can also enter a record for the hostname www.example.com as well as employees.example.com, if we are editing the records for Example.com. These are all separate hostnames, and, with their own DNS records, can point to different hosting servers or computers, if we wish them to, or even to other websites entirely.

在这种情况下，主机名实际上只是指您要去的特定位置。 根据我们的说明，如果有一个名为example.com的网站，则输入时没有任何www. 或它前面的任何其他内容，我们在编辑域记录时都使用符号@ ，以表示我们所指的是“裸域”-不带任何前缀。 如果我们正在编辑Example.com的记录，我们还可以输入主机名www.example.com和employees.example.com的记录。 这些都是单独的主机名，并且如果拥有它们自己的DNS记录，它们可以指向不同的托管服务器或计算机，甚至可以指向其他网站。

生存时间 (Time to Live)

DNS records have a “TTL” or time to live setting. This is simply an amount of time that the name servers will allow records to be cached by any of the computers who might store the information about that specific domain and hostname before that cached data must be discarded and reacquired. A low TTL means that your visitors will need to reacquire the DNS information more often, resulting in slower loads, possibly, but with always current DNS information. Longer times mean that changes to DNS may not be reflected to visitors right away, but their average load times will be a little faster.

DNS记录具有“ TTL”或生存时间设置。 这只是名称服务器将允许存储任何有关特定域和主机名信息的任何计算机高速缓存记录的时间，然后必须丢弃并重新获取该高速缓存的数据。 较低的TTL意味着您的访客将需要更频繁地重新获取DNS信息，从而可能会导致加载速度变慢，但始终使用最新的DNS信息。 时间越长，意味着DNS的更改可能不会立即反映给访问者，但他们的平均加载时间会更快。

So why is this important to us? Say that we want to move our site example.com from one host to another, but we'd like it if the change happened immediately for all users. The problem is, of course, that we've spent this whole article referring to people's browsers, computers, internet providers, and all sorts of other computers caching records about where to find a particular website. If we move our website to a new server, and update our DNS records to reflect that move - how long will it be before our visitors' computers need to check for the records again and find the new site? What if we have visitors viewing the old site? Or what if we had to take the old site down?

那么为什么这对我们很重要？ 假设我们要将网站example.com从一台主机移到另一台主机，但是如果所有用户立即进行更改，我们希望它。 当然，问题是，我们用了整篇文章来指代人们的浏览器，计算机，互联网提供商以及各种其他计算机，这些记录将有关在哪里找到特定网站的记录缓存。 如果我们将网站移至新服务器，并更新DNS记录以反映此举-访问者的计算机需要再次检查记录并找到新站点需要多长时间？ 如果我们有访问者查看旧站点该怎么办？ 或者，如果我们不得不拆除旧站点怎么办？

Enter Time to Live (TTL) settings. Before making a DNS change, if we know ahead of time, we can change our TTL to something very small - measuring in minutes instead of hours. Then, give it some time to propogate around to all of our visitors, and when we make our change, they'll be checking back very often to grab the newest dns records, and shortly after we change them, people will have that change. Then, we can raise the TTL back up, to avoid people having to send those requests down the chain so often!

输入生存时间（TTL）设置。 在进行DNS更改之前，如果我们提前知道，我们可以将TTL更改为很小的值-以分钟而不是小时为单位。 然后，给它一些时间向所有访问者进行宣传，当我们进行更改时，他们将经常检查以获取最新的dns记录，并且在我们对其进行更改后不久，人们将进行更改。 然后，我们可以提高TTL备份，以避免人们不得不如此频繁地向链下发送这些请求！

DNS记录的类型 ( Types of DNS Records )

Let's now dive into the specific kinds of DNS records that you may encounter, or have to change for your own websites.

现在，让我们深入了解您可能会遇到的或必须为自己的网站进行更改的特定类型的DNS记录。

记录 (A Records)

A records are the heart of DNS. An A Record is (more often than not) the type of record that tells an incoming request where to find the website they are looking for. One component An A Record for a domain stores an IP address for a specific hostname, such as:

记录是DNS的核心。 A记录（通常是）是一种记录类型，它告诉传入的请求在哪里找到他们要查找的网站。 一个组成部分：域的A记录存储特定主机名的IP地址，例如：

• @ (no hostname, just the domain example.com@（没有主机名，只有域example.com
• www (www.example.com) www（ www.example.com ）
• employees (employees.example.com) Note that sometimes, people redirect either their naked domain (@) or their www hostname to the other, using a CNAME record (discussed below). Sometimes, they leave both as A records and deal with the redirecting on their web server. In any case, you should definitely have both records, it’s just a question of what you do with them.雇员（ employees.example.com ）请注意，有时人们会使用CNAME记录（如下所述）将其裸域（ @ ）或www主机名重定向到另一个。 有时，它们既保留为A记录，又处理Web服务器上的重定向。 无论如何，您绝对应该同时拥有两条记录，这只是您对它们进行处理的问题。

CNAME记录 (CNAME Records)

A CNAME record (Canonical Name Record) is pretty straightforward, as well. You provide another domain name as the value of this record, and the domain name lookup process will simply continue with the new domain name. An example: If we used employees.example.com as our employee site address, and decided to alter its address, we might use a CNAME record to redirect it, and so the CNAME would have host: employees.example.com and its value would be example.com to redirect to example.com.

CNAME记录（规范名称记录）也非常简单。 您提供另一个域名作为该记录的值，并且域名查找过程将简单地继续使用新域名。 示例：如果我们使用employees.example.com作为我们的员工站点地址，并决定更改其地址，则可以使用CNAME记录来重定向它，因此CNAME将具有以下主机： employees.example.com及其值将example.com重定向到example.com 。

Why would we want to use CNAME records to redirect a hostname to another? Some people use them to redirect www. traffic to a "naked domain". Others use it to redirect the "naked domain" (@) to a www. hostname. There are also situations where we've been using a URL like employees.example.com - but now we want it to go somewhere else, without setting up a redirect on our hosting server (because we don't want to, or can't). We can easily do that with a CNAME.

为什么我们要使用CNAME记录将主机名重定向到另一个？ 有些人使用它们重定向www. 流量到“裸域”。 其他人使用它将“裸域”（ @ ）重定向到www. 主机名。 在某些情况下，我们一直在使用诸如employees.example.com类的URL，但是现在我们希望它可以转到其他地方，而无需在托管服务器上设置重定向（因为我们不想这样做，或者可以这样做）。 t）。 我们可以使用CNAME轻松地做到这一点。

MX记录 (MX Records)

MX records help mail requests to a domain find the correct mail transfer agents that are available for it. Registrars that provide free mail forwarding set this process up for you, and likewise if you buy email from your registrar, it should be set up for you. If you self host your email, or use an external service (Like Google Apps or Office 365), you may have to set up your own MX records. MX records identify the servers (mail servers) that you will use to process your mail. Sometimes there are multiple servers listed. The trick with email is that sometimes, you only get one chance to receive an email. A visitor to your webpage who has a minor connection issue can, if they choose, refresh the page or come back again later. Email might bounce and never return if a server has an issue - so there can be more than one.

MX记录可帮助对域的邮件请求找到适用于该域的正确邮件传输代理。 提供免费邮件转发的注册服务商会为您设置此过程，同样，如果您从注册服务商处购买电子邮件，则应为您进行设置。 如果您自己托管电子邮件或使用外部服务（例如Google Apps或Office 365），则可能必须设置自己的MX记录。 MX记录标识将用于处理邮件的服务器（邮件服务器）。 有时列出了多个服务器。 电子邮件的窍门是，有时您只有一次机会收到一封电子邮件。 如果您的网页访问者的连接有次要问题，可以选择刷新页面或稍后再返回。 如果服务器出现问题，电子邮件可能会退回并且永远不会返回-因此可能会有多个。

Email servers can exist on the same hosting service that you have for your website, or they can be through a whole other company, as stated above. If you were to switch to Google Apps, for instance, you might end up with MX records that look like this:

电子邮件服务器可以与您在网站上使用的托管服务相同，也可以通过其他公司来托管（如上所述）。 例如，如果要切换到Google Apps，最终可能会得到如下所示的MX记录：

Priority    Mail Server
1            ASPMX.L.GOOGLE.COM.
5            ALT1.ASPMX.L.GOOGLE.COM.
5            ALT2.ASPMX.L.GOOGLE.COM.
10            ALT3.ASPMX.L.GOOGLE.COM.
10            ALT4.ASPMX.L.GOOGLE.COM.

其他DNS记录 (Other DNS Records)

There are other types of DNS records, but these are the ones that seem to be encountered most often in the wild. There is a relatively complete listing at this Wikipedia page on Top Level Domains.

还有其他类型的DNS记录，但是这些似乎是在野外最常遇到的记录。 在Wikipedia页面的“ 顶级域名”上有一个相对完整的清单。

旁：自定义DNS服务器 ( Aside: Custom DNS Servers )

Due to a want for greater speed or more reliability, some people change the DNS servers (meaning the recursive DNS servers discussed above) that are assigned to their computer (remember, by default, this is usually our ISP's DNS servers, as discussed above), or to their router if they have one (which sets DNS servers for all of the computers on the router’s network). We could then choose a third party such as Google Public DNS or OpenDNS instead of using our ISP’s DNS servers.

由于需要更高的速度或更高的可靠性，某些人更改了分配给其计算机的DNS服务器（即上述递归DNS服务器）（默认情况下，请记住，这通常是我们ISP的DNS服务器，如上所述）。 ，或如果它们有一个路由器，则返回到其路由器（这将为路由器网络上的所有计算机设置DNS服务器）。 然后，我们可以选择第三方，例如Google Public DNS或OpenDNS，而不使用我们ISP的DNS服务器。

Once we make that change, now, when our browser and our computer cannot find a record, instead of reaching out to the recursive DNS servers owner by our Internet provider, they will instead reach out to Google's Public DNS servers (which are the exact same type of "recursive DNS server" - just owned and operated by Google rather than by our ISP). Making this happen is a matter of logging into our router and swapping the numbers around. But most of the time, people just stick with their Internet provider, for simplicity’s sake - or because they don't know there are sometimes faster or better options out there.

一旦我们进行了更改，现在，当我们的浏览器和计算机找不到记录时，它们将与Google的公共DNS服务器（它们完全相同）联系，而不是由Internet提供商与递归DNS服务器所有者联系。类型的“递归DNS服务器”-由Google而非由我们的ISP拥有和运营）。 要做到这一点，只需登录路由器并交换数字即可。 但是大多数时候，人们只是为了简化起见而坚持使用Internet提供商-或者因为他们不知道有时那里会有更快或更佳的选择。

结论 ( Conclusions )

And that’s our overview of the process and of DNS records themselves. Of course, the Internet and DNS resolution is a very muddled thing, and sure to change with the onset of IPv6, which is slowly going to be replacing IPv4 - or even with the onset of new, HTTP replacing ideas like IPFS.

这就是我们对过程和DNS记录本身的概述。 当然，Internet和DNS解析是一件非常混乱的事情，并且一定会随着IPv6的出现而改变，而IPv6将会慢慢取代IPv4-甚至随着新的HTTP替代思想（如IPFS）的出现 。

But for now, this is the process, and this was a summarized explanation of how DNS really works.

但是现在，这就是过程，这是对DNS实际工作方式的概括说明。

翻译自: https://scotch.io/tutorials/dns-explained-how-your-browser-finds-websites

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