How to prevent DNS downtime?

Everybody wants to avoid DNS downtime! Unfortunately, it affects your reputation, annoys your loyal and potential clients, and costs you money.

DNS downtime is the time your domain name won’t be resolved to its corresponding IP address. During that time, clients won’t be able to use your service or load your domain. An error will be pointed out every time they request it.

The Domain Name System (DNS) is the keystone for the Internet to work. No matter its dimension and importance, it also suffers from vulnerabilities, hacking attempts, software and hardware issues, networks’ problems, database corruption, etc. And if it stops, your domain also will.

How can you prevent DNS downtime?

To know that prevention is possible, it’s always good news, especially when your investment is at risk!

  • Set up a higher TTL (time-to-live) on your DNS records. Recursive servers’ job involves looking for updates on authoritative name servers. If you configure a high TTL value, recursive servers will look for updates less often. But with a low TTL value, they will look for updates more frequently. A low TTL is really convenient when you modify or edit DNS records because it accelerates the propagation process. If you don’t need constant changes, keep a higher TTL to avoid downtime. If your authoritative name server fails, a high TTL increases the chances for a copy of your DNS records to remain longer in the cache of a recursive. Thus your domain will still be loaded for clients, and you get more time for fixing the problem.
  • Use Secondary DNS servers. Increase redundancy while adding Secondary servers to your DNS network. More copies of your DNS records will be stored through this action, and you will manage your traffic more efficiently. No matter if your Primary DNS server gets suddenly in trouble, the Secondary ones will answer your clients’ requests.
  • Monitor the DNS server exhaustively. Every uncommon traffic pattern can mean something important. Get a proficient monitoring tool. Some can show you almost in real-time the information, by region, country, continent, etc., for you to diagnose the problem, its origin, and react.
  • Enable DNS Failover. This is an ideal teammate for monitoring, and due to its flexibility, it can be configured with the most convenient parameters for your business. Data obtained from monitoring can be connected to the DNS Failover. If a DNS nameserver fails, DNS Failover will automatically redirect the traffic from the server facing the issue to a healthy one. DNS resolution will continue working, despite your server’s problems.
  • Use DNS load balancing. This is a useful mechanism for distributing traffic across servers. For working, it considers factors such as the number of active connections, connection time, etc. By having two or more servers, DNS load balancing will manage traffic, for servers to have kind of the same amount of work, not to be sluggish or very stressed. It’s an efficient way to manage traffic spikes that can be normal or a symptom of malicious activity in progress. It directly boosts performance, prevents security issues and downtime. If a server fails or gets compromised, another will answer your clients’ requests. 
  • Strength your defenses against DDoS attacks. These threats involve enormous amounts of traffic overwhelming your system. Anti-DDoS technology protects your servers to resist such traffic.

Conclusion

You can prevent DNS downtime! There are easy or more complex alternatives. Your business’ needs will define the right one or the appropriate combination of them. Decide it today, and keep your business always up!

TTL (Time To Live) explained

We live in an environment where time is probably one of the most critical factors in our everyday life. Computing and networking are not any different. Many of the processes frequently must happen in a specific period of time. Here comes TTL in hand. In some cases, the task should be finished in milliseconds. Can you imagine that? Let’s make things a little bit more precise and explain what TTL actually is?

What is TTL?

TTL is the short acronym for time-to-live. It refers to the value that points to the exact period of time or number of hops that the data packet is configured to be alive on a network. In some cases, also in the cache memory. When that time expires, or it hops the number of times, routers will discard it. There exist many different varieties of data chunks. Every and each of them operates with their particular TTL. That means the time such data will be held in a device to function or finish a certain task.

How does it work?

If the massive amount of packets is not controlled, they will travel around routers permanently. The way to avoid this is with a limit of time or expiration on every data packet. This allows understanding how long they have been around and track their route on the Internet.

Packets travel through network points with the purpose of reaching their final destination. There is a spot inside the data packets’ design where the TTL value is placed.

Routers receive the TTL value inside the packet. It will pass to the next network point if there is spare time or hops. But if the value of TTL shows that there is no more remaining hops/time, routers won’t pass it anymore.

Instead, routers will send an ICMP (Internet Control Message Protocol) message. This type of message is used to report IP errors or diagnoses and directs to the IP address source, which issued the packet.

It will take a specific time for every ICMP message to arrive at the source. During that time, it is likely to track the hops it made while alive on the network.

TTL and DNS 

TTL in DNS finds its place for the time that the DNS resolvers have to keep the DNS records in their cache. Every DNS record has its assigned TTL value. When it is of the record is longer, there is less chance that the value will change. Therefore other records with a lot and often changes will be with a shorter value.

And because DNS requests are also packets of data, they have their TTL value inside. It would be a very interesting case if they didn’t have such limitations. DNS queries would constantly go from server to server and never finding a destination. TTL value acts as a stop mechanism of a DNS request and prevents endless search for an answer and pointless stress on the Domain Name System. The value begins with a larger number and gets decreased until it comes to zero by the routers.