DNS outage explained

You have to pay urgently to some providers, and after several tries, your bank website is unreachable. You have been chasing a promotion to renew some equipment. The promotion appears, but when you try to load the website, you receive only error messages. 

As clients, we all have experienced this more than once. We hate the website, and we don’t feel like giving it another chance. It will take a long time to forget the bad experience.

On the other side, as online business owners, we don’t want to suffer this because we understand its cost for our pockets and reputation!

What is a DNS outage?

DNS outage, also known as DNS downtime, is that period of time the DNS is not working.

You know that the resolution process is vital for accessing your domain name. If DNS fails, the process to translate it to its IP address won’t be possible. Therefore, your website could not be located, so its content won’t be reachable.

What can cause a DNS outage?

There are different causes for the DNS to fail.

Human errors. 

Misconfiguration for sure could lead to a DNS outage. And it can happen both to experts and novices. For example, a single mistake while typing the domain name’s IP address, a script error, or something wrong while setting up a firewall can be enough for the DNS to stop working. 

Having only one authoritative name server.

Businesses can definitely work with a single authoritative server. Especially small and medium ones take such decision. But the lack of redundancy can mean DNS outages every time that server requires the normal maintenance, updates, fixes, or suffers a cyber attack. That’s why having a secondary DNS server is widely recommended for answering queries uninterruptedly. 

Technical or climate problems on data centers facilities.

No matter the provider and type of service you pick, your authoritative name server (one or more) will live in a data center. Accidents, technical failures (electricity outages), and extreme weather (floods, fire…) can affect those places.

Again, redundancy is the choice not to suffer a DNS outage. If a tragedy occurs in a data center and kills the authoritative name server you had there, you hopefully have another in a different location. That way, the resolution to queries won’t be interrupted. 

Delays while propagating updates or changes. 

Editions, clearing, or adding to your business DNS records can be frequently required as a part of your normal operation. Unfortunately, such changes take time to be propagated to every machine on a network, especially if it’s a big one. 

In the meantime, for instance, an old IP address can still be saved in recursive servers’ cache. Then, when they take clients’ queries, they can provide this IP address, and it won’t work. Until they get the update, meaning that the operation will get back on track when the propagation process gets completed successfully.

Talking strictly, this is not a DNS outage. It’s not a DNS failure. But it will be perceived that way by the clients that won’t reach your domain name. 

DDoS attacks.

This is an extreme cause of DNS outage but, sadly, a possible one. Those attacks’ objective is to shut down your domain name by overwhelming your DNS servers with huge traffic loads.

DDoS prevention is crucial. An efficient solution for load balancing is a good investment!

Recommended article: ​DDoS-protected DNS service: Why do you need it?


A DNS outage is like a heart attack for your online business. Don’t allow this to stop your operation and damage your image. Instead, be aware of its causes, to prevent them on time! 

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