How does rDNS (Reverse DNS) work?

After you set up your Forward DNS and add your DNS records, it is a great idea to set up a rDNS (Reverse DNS)! When you try to send an email from the domain, you will probably notice a problem. Your emails will go missing or to the SPAM folder. And this is something nobody wants for their business. So, now let’s explain a little bit more about rDNS (Reverse DNS).

What is rDNS?

Reverse DNS is also known as rDNS. It has the opposite purpose to a Forward DNS, which is to map IP addresses to hostnames. The main reason for using the Reverse DNS is to implement a way to verify the IP addresses and prove that they are related to a particular domain name. It is mainly necessary when we are talking about the verification of mail servers or other services. 

It lets you create a Reverse DNS zone, where you can add PTR records and use them as confirmation that the IP addresses and the domain name matches.

In short, let’s put it this way:

In Forward DNS, a domain name is pointing to an IP address where it is hosted.

In Revere DNS, An IP address is pointing to a domain name to verify it belongs to it.  

Master Reverse Zone

To be able to use Reverse DNS, you will need to create a Master Reverse Zone. IP addresses should be written in reverse. The rDNS can work both with IPv4 addresses as well as IPv6 addresses. Also, later you can add the PTR DNS record. The Master Reverse Zone will be the place where the PTR record can exist. 

PTR record

PTR record, also known as pointer record, produces the mapping we need: IP address to hostname. 

For each PTR record, you will need an A or AAAA record. 

You will need the PTR records and the Reverse Zone to verify the outgoing mail servers. During the process, there will be a check of both the PTR records and the A records. 

You have to make sure that your DNS records are set up appropriately. Your emails will most probably go to the spam folders if they are not arranged correctly. 

Slave Reverse Zone

If you want, you can create a Slave Reverse Zone. It is just a copy of the Master. A Slave Zone is always read-only. You can make changes only in the Master Reverse Zone. 

Slave Reverse Zone can serve you for providing redundancy or faster response if it is in a DNS server closer to the users. 

How to check your Reverse DNS?

You can check your Reverse DNS by examining the IP addresses and see if they lead to the hostname. There is a simple way to do it. On most of the OSes (Linux, macOS, Windows, etc.), you only have to use the Nslookup command:

nslookup 192.168.1.2

Just replace the IP address, in this example, is 192.168.1.2, with the one you want to verify. In this case, it is an IPv4 address, but that doesn’t mean that you can’t put in an IPv6 address too. 

So now you know how simple and easy it is.

What is a DNS TXT record?

What is a TXT record?

The TXT record is a type of DNS record that has TXT-DATA filed with instructions that can work with existing DNS servers. The actual text is formatted, so it has an attribute name than a value for that attribute, and the “=” sign separates the two. The most common way of TXT record use is for email verification, but it also servers for various verification and authentication methods. Some services (Google Apps, Microsoft Office 365, and more) will ask you to add such a DNS record to your zone to prove that you have control over your domain.

How does TXT records work?

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DNS load balancing: What is It and Why Do You Need It?

What is DNS load balancing all about? Well, the fact is that you can’t allow a web server to overload. If your business website has a slow and faulty network, it will definitely impact the end-user experience. It will cause poor perception of the site and so on to your organization. 

Therefore it is important to implement a load balancing method when you are managing your network.

What is DNS load balancing?

DNS load balancing is a technique for administrating the traffic of a hostname. It is about troubleshooting the distribution of inbound network and application traffic across multiple servers.

Websites with a lot of traffic are operating with many requests from users or clients. For every request, they have to return the exact and correct text, images, video, or application data, all in a fast and safe way.

DNS load balancers are intelligent. First, they use various criteria and examine the traffic. Next, they decide to let the traffic proceed or stop it and redirect it to a different server based on the current packet load or another parameter. 

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How does Anycast DNS work?

The Domain Name System (DNS) is one of the foundations of the Internet, yet most people outside of networking probably don’t realize they use it every day to do their jobs or check their email. Anycast DNS helps using the Internet to be even faster and efficient. Let’s talk about that a little bit more.

What is Anycast DNS?

When you choose Anycast DNS as your routing method, you can establish your IP address in several DNS servers.

Through Anycast, different servers positioned in many geographical locations are capable of answering the query. The closest of them will provide the IP address to the user. 

Also, if one of the DNS servers is down for some reason, the second closest server will receive the request. 

Experience is faster and better with Anycast DNS when we speak about loading time, waiting for a response, etc.

Before we continue, let’s explain a little bit more about what DNS is.

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FQDN (Fully Qualified Domain Name) Meaning

FQDN looks like another abbreviation that seems complicated to pronounce. It stands for Fully Qualified Domain Name, and let’s clarify what does it means. 

What is FQDN (Fully Qualified Domain Name)?

The term “fully qualified domain name”, FQDN for short, sometimes also associated with an absolute domain name, is a domain name that defines its exact location in the tree hierarchy of the Domain Name System. It specifies every domain level, including the top-level domain and the root zone. It is the most comprehensive way to write a particular domain name for a host or a computer.

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What is a Web redirect record, and how to use it?

What is it?

The web redirect record can redirect a request for one URL to another URL. It is also known as URL redirect or HTTP forward and is often written as WR record.

You can use it to make a particular web page available on multiple URL addresses.

There are two types of web redirects:

  • 301 redirect. This redirect is permanent. You will be showing that the URL that was before is already gone for good, and this is the new location of the page that the search engines should learn. Eventually, the search engines will forget the previous URL and remember the new one.
  • 302 redirect. This redirect is temporary. It will tell the search engines that they should not forget the URL and just give it some time to get back. During the time the URL is not working, the traffic can be redirected to the main page or to another. If it is a product page, you can direct to a similar one, so you don’t lose sales.

What’s inside a Web redirect record?

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Dynamic DNS (DDNS) explained 

What is Dynamic DNS (DDNS)?

The DDNS abbreviation stands for Dynamic Domain Name System. While the typical DNS can link domain names to IP addresses via A or AAAA DNS records, the Dynamic DNS can automatically refresh and change the host’s IP address, so even if its IP address changes, the clients can reach it.

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How to make my website more secure

Threats on the Internet are many, and they come with different disguises. Dealing with such risks daily is part of the online adventure for websites’ owners. Everybody, big, medium, and small businesses, can be targeted. The best practice is not to underestimate the importance of securing your business website.

Fortunately, there are different actions you can implement to make your defenses more robust. Let’s check some.

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SPF record explained 

What is SPF (Sender Policy Framework)?

There are various ways that cyber-criminals can forge emails. They can modify the “Mail from” and make the emails look like they are coming from a specific domain when they are not. The SPF. Sender policy framework protocol is here to put strict rules. With SPF, the domain administrator can strictly limit who can send emails from the domain. The other part, the receiver, has a mechanism to check the authorization and take the necessary measures.

The outcome of the SPF evaluation can be:

  • None – No SPF record was found, or the record was not properly configured.
  • Neutral – The DNS admin is not stating that a particular IP address is authorized.
  • Pass – The client is authorized to inject emails with the identity provided.
  • Fail – Not authorized to use the domain.
  • Softfail – Probably not authorized. There is a stronger “Fail” missing.
  • Temperror – Currently, there is an error, most probably related to the DNS. Later, if retry again, the problem could be gone.
  • Permerror – Permanent error. The DNS admin must fix an error because otherwise, the SPF record could not be understood.

Why do you need a DNS SPF record?

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