What Is An External DNS?

You’ll need to update the domain nameservers if you switch hosting providers. This is because your website files will now be hosted on a different server. All of the lookup databases may take up to 48 hours to update. 

This is referred to as propagation. Furthermore, if a web server is targeted by a Distributed Denial of Service (DDoS) assault, the DNS server and the central server may also be targeted. To address these big problems, you might wish to explore having your DNS records handled outside of your server.

External DNS is the service that translates domain names to IP addresses. It’s what makes your browser know where to find certain websites. Some people use it for privacy, while others do it because they want their business website to appear in a different location than its physical address. When you set up an external DNS, there are some things you need to think about before making your final choice. For example, will this be something I’ll have forever? Am I worried about data security? This blog post will help answer all of these questions so that you can make an informed decision!

What Is DNS?

DNS stands for Domain Name System. This service has been around since the 80s and is responsible for translating domain names (like “google.com”) to IP addresses (the string of numbers that tell your browser where to find something). 

We all interact with DNS many times a day, whether we mean to or not! For example: when you type in the web address of a website into your browser, DNS does its magic and translates that to an actual IP address.

Above is what our world looks like when mapped out with all domain names converted into their corresponding IP addresses. Can you imagine how difficult it would be if we had to look up all of these numbers every time we wanted to visit “facebook.com” or “twitter.com?

What Is The Purpose Of External DNS?

External DNS, sometimes called “custom DNS” or “public DNS,” is a way to use an alternative service for translating domain names into IP addresses. 

It has become more popular recently due to privacy concerns (more on that later). When you set up your own external DNS service, you take the place of the ISP’s default system and act as the gatekeeper to your domain names. 

This has an added benefit of speeding up lookups because you are likely closer (in network terms) to the person who is making the lookup request than the ISP’s DNS system would be.

How Does External DNS Work?

Let’s say that someone on your network wants to visit “google.com.” As mentioned above, DNS is responsible for translating the domain name into an IP address to be routed over the internet. When a query comes in from one of your devices, you have two choices:

When you choose option #A and use Google Public DNS, you’re just delegating your DNS service to Google and asking them for the IP address of “google.com.” It’s as simple as that!

When you choose option #B and use OpenDNS instead, things are a bit different. Your device will first check its local cache to see if it already has an answer stored. If the answer is not in the local cache, it will request OpenDNS’s servers. 

The server then checks its DNS records for an answer before asking other nearby name servers if they know anything about this domain name. Once all of these queries are complete and there’s no cached or stored answer, your device gets back to you with an IP address.

What Happens When I Use An External DNS Service?

When using any third-party (external) DNS service, there will be a slight delay before your device starts using the new settings. Your ISP’s DNS system will likely still be cached for a while (or indefinitely), so you may notice some lag when switching to your custom service.

What Are The Benefits Of External DNS?

There are many reasons why you might want to choose a third-party service for your external DNS needs, but privacy is perhaps the most important one.

Here’s what comes down to data that passes through ISP networks can be seen and changed at will (even if they do not own the content). This is how ISP’s can throttle your bandwidth or monitor illegal downloading activities.

Many people choose to use a third-party service instead of their ISP for DNS queries to keep data secure and private

The benefit here is that you do not have to worry about anyone seeing what sites you visit (or trying to block them) because your queries are encrypted and go directly to the third party’s servers. Furthermore, since these services usually have many data centers worldwide, you can choose the one closest to you for fast lookups. If this made you want an external DNS, see our article “How To Create A DNS Server?“.

What Are The Downsides Of External DNS?

Using third-party DNS services can cause problems in certain situations because they don’t know the local network’s structure or how devices are configured. 

This can cause problems for some services that make their internal name resolution (mail servers, chat programs, etc.). For these reasons, you will sometimes need to set up exceptions, so your device doesn’t try looking up domain names through its ISP but instead uses the external DNS service exclusively.


Having your own external DNS service is a great way to improve the privacy of all your queries. It’s also faster than using an ISP’s name servers because they are usually farther away from you geographically (making it take longer to get an answer back). They do not have access to this data and cannot see what sites you visit or share that information with anyone else.

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