How does browser resolve dns

Learn more. Asked 7 years, 9 months ago. Active 7 years, 9 months ago. Viewed 10k times. Improve this question. Concordus Applications Concordus Applications 2 2 silver badges 7 7 bronze badges. Do you have a proxy server configured in your browser? If your browsers are configured to use a proxy server, then DNS isn't performed on the local machine, the proxy server does the DNS resolution. Hi Zoredache, Just curious, will it be the case.

I trust that even after configuring proxy, the resolution should be done by resolv. Though I haven't tested it and I am just saying this out of logic from my mind. Please correct me if I am wrong. In most cases, if the user has recently accessed URLs of the same domain, or other users relying on the same DNS resolver have done such requests, there will be no DNS resolution required, or it will be limited to the query on the local DNS resolver.

We will cover this in later articles. The end user has no idea what is happening behind the scenes; they are simply are waiting for the page to load and all of these DNS queries have to happen before the browser can request the webpage. This is why we stress the importance of fast DNS.

You can have a fast and well-built site, but if your DNS is slow, your webpage will still have poor response time. Start a Trial Log In. Catchpoint Platform. Monitoring Use Cases. Synthetic Monitoring. Monitor everything from development to production that can affect your end-user experience. Real User Monitoring. Sign up or log in Sign up using Google.

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Does ES6 make JavaScript frameworks obsolete? Podcast Do polyglots have an edge when it comes to mastering programming Featured on Meta. Now live: A fully responsive profile. Related 2. Hot Network Questions. Question feed. Stack Overflow works best with JavaScript enabled. 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! 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. 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. 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.

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. 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. 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 root name servers redirect our request to the name servers for our requested top-level domain TLD. Each domain ending like. 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. There used to be only a handful of top-level domains TLD like.

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.