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5 Dig command examples

Dig command (domain information groper) is a built-in command that you can find in any macOS computer and most Linux distros. You can use it to perform a quick check related to your DNS. See individual DNS records or check a name server from the Terminal app with a simple 1 line command. 

It might not have a graphical interface, but you will get all you need in its output.

Here you have 5 dig command examples that will show you how to use it and how the answers look. 

How does Dig command work?

5 Incredible Ping command Examples

Today we will explore the Ping command. First, we will explain its definition and how you can use it. Finally, we will discover the five most popular Ping commands. Let’s start.

Definition of the Ping command

One of the built-in network diagnostic commands in your operating system is the Ping command (Windows, Linux, macOS, FreeBSD, etc.). Ping is used to test connectivity between your device and the target, which can be an IP address like or a hostname like

By default, Ping uses the ICMP protocol to send the target four messages, each containing 32 bytes (Internet control message protocol).

Brief History of Ping command

Purpose and Advantages of GeoDNS

GeoDNS is the topic of today’s article. First, we will explore it in detail: its purpose, how it works, and its advantages.

GeoDNS – what is its purpose

GeoDNS stands for global traffic director or simply traffic director. It is an effective method for optimizing traffic to domains through the use of geographically based routing. It is also regarded as a cloud alternative for load balancing. In addition, it has a positive impact on network performance.

5 DNS records you should know 

What are the DNS records?

DNS records are text-based instruction for name servers (DNS servers) that can serve to link hosts to IP addresses, IP addresses back to hosts, services to hosts, one name of a host to another, combine to have complex rules, and more. 

There are some DNS records that are quite essential for the DNS functionally. Here are the first you should learn.  

The 5 DNS records you should know are:

A record

A record is the first that you think about when you are talking about DNS. It links domain name / hostnames to their IP addresses. When somebody wants to visit a site, they usually know its name (domain name). But what they actually need to find it is its address. The visitor’s browser will go on a long search, from one DNS server to another, until it gets the A record that resolves the query. It gets it back, and the browser knows already where the site is and can load it. 

SOA record

This is the start of authority record, which indicates the primary DNS server – the authoritative name server. It also contains information about the DNS zone, and it is a must-have for the normal functionality of your DNS network. Inside it, you can find out which is exactly the authoritative server, who is responsible for it, how often should the DNS server refresh, and more. 

PTR record

It is a bit neglected DNS record, but it is a must-have if you want to send emails without problems. The PTR is a pointer record that has a functionality opposite to the A record, and it serves for Reverse DNS. It can point an IP address to a domain name. Why do you need it if people don’t remember IP addresses? For the machines! Because when you send an email, the receiver will want to check if this email was really sent on behalf of the domain it is saying or no. If the A record and the PTR record are not configured properly, the emails will go to spam. It can work both with IPv4 addresses and A records or with IPv6 addresses and AAAA records. 

Why do you need a PTR record?

Dynamic DNS – Common ways to use it

For many people, using a Dynamic DNS could be really advantageous. Put simply, this DNS service is a method for automatically refreshing new IP addresses. We’ll look at what Dynamic DNS is and how it works in more detail in this article.

Dynamic DNS – What does it mean? 

Dynamic DNS, also known as DDNS, is a very useful service that allows us to keep the DNS constantly updated, with the correct IP address, even when the Internet Protocol is changing. Commonly, these kinds of resources include a Web server, a Web camera, or a computer for remote control operation.

What is a DNS NAPTR record?

DNS NAPTR record explained.

The DNS NAPTR record is a Name Authority Pointer record that helps with mapping servers to the users’ addresses in the Session Initiation Protocol or SIP for short. The NAPTR records, together with a different type of DNS record named SRV (service) record, let the chaining of various records set complex rewrite rules. As a result, they produce new domain labels or Uniform Resource Identifiers (URIs).

Based on the flag of the recently designed URI or domain label, it is possible to be applied in the following query for a DNS NAPTR record. It could also be straight as an output of the complete process for URI mapping.

When the DNS NAPTR record is present, it lets lookup at services for various different resource names such as URIs. These, in other cases, are not usual pieces of a domain name syntax.

How to check the NAPTR record?

How to use NSlookup commands

NSlookup is a built-in software that allows you to query domain name servers.

NSlookup commands can be used on most typical OSes like Windows, macOS, and Linux (Ubuntu, CentOS, Debian, etc.). Now you will see what is it, and how to you it?

How to start the NSlookup command?

For Windows

1. Press Windows key + the letter “R”. This will start the run application.

2. Write “cmd” and press “ok”.

3. Now, you are ready to use NSlookup command. See the examples below.

For macOS

1. Press the command button + Spacebar button.

2. Type the name of the app – Terminal.

3. Ready to write NSlookup commands.

Nslookup: command not found – how to fix it?