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How to prevent a DNS leak with a VPN?

Prevent DNS leak with VPN

Today, the internet is a dangerous place to be. While many don’t feel or even understand the prevalent issues regarding the dangers associated with the net; Numerous users try to make their digital lives safe with all their might. One such tool that can aid users on the quest to internet safety is undoubtedly the VPN. A VPN can secure your data and keep you hidden on the internet. But is employing a VPN enough to prevent problems like a DNS leak?

VPNs are not foolproof or all-powerful, especially when extenuating issues are prevailing. One such wrench that can render a VPN useless is the notorious DNS leak. If your VPN is leaking, all your effort is for naught. But what is a DNS, and why do DNS leaks matter? Also, is there a way to prevent a DNS leak when using a VPN? Let’s find out!

What is DNS?

DNS, or Domain Name System, is a decentralized naming system for online resources, such as computers and other services. We know that everything connected to the internet has a unique digital identity. This identity establishes communication on the network amongst different devices. This is precisely what we call an IP address. But IP addresses are mostly a long string of numbers or alphanumeric in nature. Now, when a user wants to access the resources on the internet, they have to connect to the particular device via the IP address. However, it is impractical to remember such long numbers. That’s when DNS comes into play.

In simple words, DNS translates IP addresses into something possible for the user to understand and remember. That’s right! Take the domain name of a particular website, for example, “Facebook.com” Now we know that entering this specific name into the web address bar will take us to the Facebook website. But how? We didn’t enter the IP address for the site. Also, we know that every website has an IP address that is essential for connection. Well, we know that In the background; while we typed “Facebook.com,” DNS converted the domain name into an IP address that allowed the browser to connect to the website.

Thus, a DNS essentially converts an IP into a domain name and vice versa to make internet communication feasible. DNS is a series of servers and computers that connect domain names to corresponding IP addresses. To do so, they utilize a process known as the DNS lookup. Just like a phone book, the DNS converts numeric and alphanumeric content into (domain) names for easy access.

How does it work?

Here is the simplified process outlining the DNS lookup:

  1. A user enters the web address into the browser.
  2. The browser requests the OS to locate the corresponding IP address.
  3. The operating system now forwards the request to the ISP (Internet Service Provider). Important to note here that the ISP has a DNS server configured, known as the revolving server.
  4. The revolving server finds the location of the top-level domain nameservers. These nameservers are in control of the DNS records of the requested hostname. With this hostname lies the IP address.
  5. The revolving server receives the response and forwards it to the ISP. It then gives the record and the corresponding IP to your OS.
  6. The operating system transfers the information to the browser that uses the IP to locate the website. All these steps happen in microseconds.

What is a DNS leak?

DNS is by default visible to your ISP. If you use the internet as you do without an attempt at hiding your activities, it is a generic process of DNS lookup. However, every ISP records and logs DNS activity to monitor data traffic. Moreover, in extreme cases, it engages in data mining and selling. Thus, those who value their privacy use tools like SOCKS5 proxy, The Onion Router (TOR), or VPN to hide from the prying eyes of the ISP.

Now, in the case of VPNs, the technology masks your original IP and encrypts your data. They use remote VPN servers to access the internet on behalf of the VPN client. In this case, a user must feel they have done enough to ensure their privacy, i.e., they are wholly safe. Wrong! Unless and until you can ensure your real DNS is not leaking, you won’t be hidden.

Thus, a DNS leak is the exposure of your DNS requests despite you wanting them to remain concealed. You employ a VPN to hide your IP and corresponding data to avoid trackers. But sometimes, it fails to do so. That’s because of the DNS leak. The data routed for the VPN ended up showing at the ISP due to a DNS leak. Thus, a DNS leak is a security flaw that allows your data to reach the default DNS servers belonging to the ISP instead of your VPN.

Why does a DNS leak matter?

The reason a DNS leak can be a disaster is that it can mitigate all your attempts at ensuring privacy. We know that an exposed DNS can allow an ISP to know what we are doing even with an active VPN. Furthermore, it can lead to VPN blocking. Thus, ensuring your safety is directly proportional to the absence of a DNS leak.

If you are worried about privacy and trying to remain safe on the internet, it is paramount you prevent any leaks. Once again, these leaks can lead to third-party snooping, data mining, and cybercrime, even with a VPN enabled.

How to prevent a DNS leak?

Now that we know what a DNS is and how crucial is it to prevent a DNS leak, let us look at the few ways we can do so:

  1. Clear DNS cache — DNS caches keep the recent browsing history. By clearing it, you can prevent a DNS leak.
  2. Disable Microsoft Teredo — Microsoft Teredo is a technology that smoothens the transition from IPv4 to IPv6, but it exposes your DNS by circumventing your VPN. Turn off Teredo!
  3. Change settings to use VPN’s DNS server by default — Change your device’s settings to utilize the DNS server of your VPN provider by default, rather than your ISP’s.
  4. Use secure DNS services — Services like Cloudflare, Open DNS, and Google Public DNS provide a secure DNS resolver. Some even encrypt your DNS data to prevent a DNS leak.
  5. Implement your firewall to block non-VPN traffic — You can always set up your firewall to deny non-VPN data access.
  6. Use a private browser — Private browsers encrypt DNS data. They prevent WebRTC leaks and can effortlessly prevent DNS from leaking.
  7. Manually set up your DNS to a nonexistent one — Manually change your DNS server to 0.0.0.0 or 127.0.0.1.
  8. Set up a personal DNS resolving server — You may set up a DNS resolver of your own.

Prevent DNS leak using a VPN

However, the best way to resolve a DNS leak is undoubtedly using a VPN. Although a DNS leak occurs due to faulty VPN implementation, some providers offer exquisite products for preventing leaks. You can always try to:

  1. Use a VPN with its DNS server — The first thing you need to do is make sure your VPN comes with an exclusive DNS server or has a feature known as Smart DNS.
  2. Ensure that the VPN has a DNS leak prevention feature — You can also employ VPNs with a DNS leak prevention feature.
  3. Use a VPN monitoring software — A VPN monitoring software will ensure your device’s traffic doesn’t end up elsewhere. It allows you to redirect any data traffic towards your VPN.
  4. Employ an automatic kill switch — Always keep the kill switch on. An effective kill switch will terminate the internet connection in a VPN failure. Thus, it will prevent leaks of all sorts.
  5. Ensure your provider offers a no log VPN policy — Before you use their VPN, double-check your provider doesn’t employ data logging practices.