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5 Dig command examples

By Bob on April 22, 2026

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?

Get the A or AAAA record of a domain name.

dig domainname.com

This command will show you the A record or the AAAA record, or both for the domain you are probing. The first will show you the IPv4 address of the domain name, the second IPv6.

Get all of the available DNS records.

dig domainname.com ANY +noall +answer

Sometimes you want to see a list of all of the available DNS records, including A, NS, MX, TXT, AAAA, CNAME SOA, and PTR records. That way, you can get a lot of information about the zone, name server, and individual records. Later you can check a particular record or server.

+noall +answer will reduce the answer to just the answer section.

Get information about the name servers for a particular domain.

dig domainname.com NS +short

You will get an answer with all the name servers (NS records). Later you can use “dig @nameserver…” to perform additional probes for a particular NS server.

Get the MX records for the domain name.

dig domainname.com MX

You can see the MX (mail exchanger) records for the hostname. From them, you will see which are the incoming mail servers. Not having MX records will be a problem for receiving emails. The senders won’t be able to find which of your mail servers are responsible for receiving the messages, and the delivery will fail.

Get the TXT records for the domain name.

dig domainname.com TXT

By performing this command, you will see all the TXT records. The common TXT records are SPF, DKIM, and DMARC. All of them are used in email for verification and authentication. They increase the security during the transfer of emails and check if the sender is really the one it says it is. You can check the TXT records for your domain and see if they are properly configured. If you have made errors, you might not be able to send and receive emails or both.

Get familiar with these examples and try to improvise by changing some of the parameters for your personal needs.

The hostname could be changed with its IP address; You can probe each individual type of DNS record and more.

Dig command can also show you the route of the query or answer reverse lookups.

Why should you use the dig command?

Because it is already on your computer and it can give you enough information about your DNS. It works fast and has a few options to get the right answers.

Dig is ideal for quick checks.

5 Incredible Ping command Examples

By Bob on July 26, 2022

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 188.114.97.7 or a hostname like google.com.

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

How can you use it?

You can use the command on Windows devices in one of two ways: through the Command Prompt or using Windows PowerShell.

And if you are using Linux or macOS Operating systems, you may use it through the Terminal application.

5 examples of Ping command

The basic Ping command allows you to check your connectivity and the capability of the computer you are testing. As a result, on Linux or macOS, you will constantly hear a ping. Use the Ctrl-C combo to stop it. If there are no problems, you will get four replies and statistics for Windows.

ping example.com

On Windows, you should add the extra option “-t” for continuous ping. Fill in the following:

ping -t example.com

For a specific quantity of inquiries. You are allowed to make a custom number of queries on macOS and Linux and more than four requests on Windows.

For Linux and Mac

ping –c 8 example.com

in Windows

ping –n 8 example.com

The space in between pings. You can calculate the time in seconds between requests.

Linux/macOS

ping -i 20 1.2.3.4

Waiting period. It can be set to stop the ping command on macOS/Linux in seconds.

ping –w 50 example.com

Conclusion

So, the Ping command is a fundamental tool for network device testing. It is available on almost every OS and functions nearly identically on each one. ICMP packets should be sent, and the duration of the echo-response should be timed. Simple and ideal.

Purpose and Advantages of GeoDNS

By Bob on April 18, 2022

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.

How does it work?

GeoDNS operates in a unique way. How? To begin, when users query your site, their requests are routed through DNS servers. If you use GeoDNS, you will be using multiple DNS servers located all over the world. This is determined by the DNS service provider you choose. That is, these servers will search their database for each user’s IP address and compare it to the information they have on file for that IP address. The traffic is subsequently forwarded to a predefined IP address, which is usually the one closest to the query’s origin.

Advantages of using GeoDNS

GeoDNS could be really beneficial. Here are some of its main advantages:

It’s simple to use. When it comes to setting it up, you will have no problems. After that, everything will operate on its own. All you need is a basic understanding of DNS.
Monitoring the DNS. One of the most critical benefits is that it could also keep track of your DNS. It might also be set up such that IP addresses on your blacklist are blocked. As a result, complications will be avoided.
Traffic redirecting. You may establish a comprehensive CDN with GeoDNS. That way, you may host your website on multiple servers and use GeoDNS to automatically guide customers to the version of your site that is closest to them. That method will also serve as a load balancer for you. Your network will run without a hitch.
Implementing Geo-restrictions. You could set geo-restrictions based on your users’ IP addresses (location). You have the option of choosing who will be allowed to see specific kinds of information. This is particularly handy when dealing with intellectual property, such as videos, music, and photographs.

Who is GeoDNS for?

GeoDNS could be an excellent solution for a variety of companies. The great majority of large organizations with a global presence, on the other hand, are likely to reap the most benefits from using this type of service. Also, content platforms that serve a worldwide audience and e-commerce websites that require a high level of uptime.

Conclusion

Let’s review. GeoDNS is a global traffic director. Its primary purpose is to distribute the traffic. Its main advantages are that it redirects the traffic, manages geo-locations, and monitors the Domain Name System. In addition, it is really easy to configure. So, it’s worth giving it a chance!

5 DNS records you should know

By Bob on March 5, 2022

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?

CNAME record

The CNAME record is used to show which is the real domain name (canonical) for domain / subdomain that you are looking for. You should know this DNS record because you should use it for all your subdomains. That way, you can just create CNAME record for them and point to the domain name without the need to create more DNS records for them. When you update DNS records for the YOURDOMAIN.com, you won’t need to update subdomain1.YOURDOMAIN.com, subdomain2.YOURDOMAIN.com, and so on. It will facilitate DNS management for you.

MX record

This record is also important for email correspondence. It is known as the mail eXchanger record. It will show which exactly is the server or servers that are responsible for accepting emails for the domain. As you can most probably guess, without this DNS record, the sending servers won’t know to who they should send messages, and you can’t receive emails. So, with the PTR, you were fixing the sending, and with the MX record, you are fixing the receiving part.

Conclusion

This is a good first step into the world of DNS. There are plenty of DNS records more, but now you know how the most important of them look like. The A, SOA, PTR, CNAME, MX are among the first that you should know and start using right away.

Dynamic DNS – Common ways to use it

By Bob on January 27, 2022

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.

The Domain Name System (DNS), as we already know, is a user-friendly and simple-to-use system for associating domains with their IP addresses. Unfortunately, these Internet Protocols are running out on a daily basis. Internet Service Providers (ISPs) are attempting to avoid this scarcity by utilizing dynamic DNS in particular. DDNS automatically logs changes from dynamic IP addresses. This ensures that domains remain connected to the appropriate Internet Protocols.

How does it work?

Most often, to take advantage of a dynamic DNS, you need to look for a provider. Then when you find it, you need to install their software on the host computer or on the router. When the IP addresses provided by the ISP are changed, this software connects with the DDNS service provider. As a result, the dynamic DNS provider updates the A record or AAAA record to reflect the changes, resulting in near-instantaneous updates.

In addition, a dynamic DNS service is incompatible with networks that use static IP addresses. This is because the domain name does not need to be asked again after the IP address is given the first time. The reason is straightforward: static IP addresses do not change.

Why do you need to benefit from Dynamic DNS?

There are many advantages. Some of which are as follows:

It keeps you online. It will reduce downtime by automatically updating A record or AAAA record. As a result, the gadgets or services will continue to be accessible via the Internet.
Incredibly simple. It only has to be set up once – for example, IP cameras for surveillance. You’ll need to configure your router’s Dynamic DNS service by heading to settings and entering the user and password.
Static IPs are more expensive. If you have multiple devices, it will be far more cost-effective to pay for only one DDNS service. It could be costly to pay for each static IP address.

Conclusion

We can conclude that it is a long and complex explanation for a very simple service that keeps millions of people connected to their devices all over the world. Remember that the DDNS method is useful in the case of dynamic IP addresses. The Dynamic Domain Name System (DDNS) is a very helpful technology that can save you a lot of time and money. It may be the only logical solution to a problem in some cases.

What is a DNS NAPTR record?

By Bob on October 12, 2021

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?

DNS NAPTR record – Why do you need it?

DNS NAPTR records function collectively with SIP and the SRV records included, also. With them, you can understand the variety of services available for a domain name. When a user makes a query for the NAPTR records, it will notice all of the protocols and ports that are applied. In addition, it will examine if they support SIP or any extra VoIP service.

Structure

The structure of the DNS NAPTR record is a little bit more complicated compared to other DNS records. However, inside it, you can view different values:

TYPE: In this case, it is NAPTR or its code, which is 35
Domain name: Here is the hostname to which it applies. This is the key for the rule database.
TTL: Here, you set the TTL value (Time to live) for the DNS record.
Order: Here, a number (16-bit unsigned integer) reveals the order by which the DNS NAPTR record must be processed to follow the rules correctly. First are the lower numbers. In case the values are identical for two or more DNS NAPTR records, the precise order is defined by the preference values.
Preference: Here, the value (16-bit unsigned integer) defines the order of DNS NAPTR records with identical numbers. Again, if the number is lower, it goes first. The distinction with the Order number is that Preference provides weight to otherwise identical rules.
Flags: Here are the flags that are written with letters. For now, there are four different flags: S, A, U, and P. With them, it is determined if there is going to be a coming lookup or not. Additionally, they show what has to be next.

S: This flag shows that the next lookup has to be for the SRV record.

A: The next lookup has to be concerning the A, AAAA records.

U: This flag shows that the next is going to be URI output.

P: With this flag is represented the protocol. It indicates that the protocol is going to define the next step.

Service: Establishes the service one or many down the rewrite path. It is also possible to be a particular protocol that is specifically applied for a service.
Regular expression: Typically, it is also called Regexp. It is a string that becomes attached to the original string. The purpose is to generate the following domain name for a lookup. It has to link the string of the customer and not regarding a prior DNS NAPTR record.
Replacement: It is based on the flag, and what is the following name (fully qualified domain name) to query for NAPTR, SRV, or different records.

Transmission control protocol (TCP) explained.

By Bob on September 9, 2021

TCP – What is it?

Transmission Control Protocol, or also for short called just TCP, is a communication standard. Software applications benefit from it for exchanging data. Its purpose is to improve efficiency, not speed.

The packets of information can reach their destination out of order or get lost when they are transported. TCP serves to ensure that they will arrive at their target and without the need to be rearranged. In case a packet is not delivered in a specific timeframe, TCP requests re-transmission. It handles the communication between the two applications through the entire exchange. It assures the delivery and sending for both parties and also verifies that packets are accurate. TCP is a popular protocol in network communication and is ordinarily used on top of IP. Usually, the Internet protocol stack is associated with TCP/IP.

Usage of TCP

Transmission Control Protocol (TCP) is one of the main components operating while we use the Internet every day. For example, when we are browsing the web or exploring a web page, the webserver is supported with the help of HyperText Transfer Protocol (HTTP) to carry the website’s file to our device.

HTTP relies on TCP to successfully connect your computer and the server and ensure that the file is transferred correctly over IP. Moreover, File Transfer Protocol (FTP) for peer-to-peer file sharing depends on TCP and Simple Mail Transfer Protocol (SMTP) for sending and receiving emails.

TCP is beneficial when the accuracy of the data transfer is more valuable rather than the speed. It applies three-way handshakes to establish the connection. So, the data is chopped into smaller packets and requests for re-transmission to ensure correctness. That is the reason the time for the data to transport is extended.

In some cases, such as video gaming and streaming, or Voice Over Internet Protocol (VoIP), TCP is not beneficial because of the prolonged latency. In these examples, User Datagram Protocol (UDP) comes in hand. It is less precise, yet it is faster.

TCP vs. HTTP

The two protocols may fool you that they are very alike, but The Hypertext Transfer Protocol and the Transmission Control Protocol have some remarkable differences.

HTTP utilizes TCP for data transfer, and TCP is a data transfer protocol.
TCP is applied to establish communication or a session linking two machines. On the other hand, HTTP is used to reach information on web pages and access websites from a web server. It’s a client-server protocol.
TCP handles IP addresses, while HTTP handles hyperlinks, also identified as URLs.
TCP process requires a three-way handshake. This requires some time. However, HTTP is a one-way connection. That is the reason why TCP is much slower rather than HTTP.
TCP is connected-oriented. In contrast, HTTP is stateless but not sessionless.
TCP utilizes various ports (80, 8000, 8080, etc.). HTTP typically uses the 80 port.

Benefits of TCP

The data delivery is guaranteed to be accurate end-to-end. The bytes received are the precise ones and in the same order as originally sent.
The functionality of TCP covers the detection of issues, such as lost or duplicated packets and the capability to fix them.

How to use NSlookup commands

By Bob on August 22, 2021

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?

Examples of how to use Nslookup commands:

Use these examples with the domain you like by changing the domainname.com with the one you like. The same goes for the IP addresses used in the examples.

Use the NSlookup to see the domain’s IP address:

nslookup domainname.com

This will show you the data from the A and AAAA records of the domain. There you can see the IPv4 and IPv6 addresses.

Check specific DNS type of record with the following:

nslookup -type=TYPE domainname.com

You can change TYPE with the type of DNS record you want to query like: A, AAAA, MX, SOA, NS, ANY (any type available).

nslookup -type=a domainname.com – shows you the IPv4 addresses of the domain.

nslookup -type=aaaa domainname.com – shows you the IPv6 addresses of the domain.

nslookup -type=mx domainname.com – shows you the MX records, and you can see the responsible email servers for receiving emails.

nslookup -type=soa domainname.com – shows you the start of authority.

nslookup -type=ns domainname.com – shows you the name servers available.

nslookup -type=any domainname.com – shows you all of the DNS records available.

Check a specific name server.

After you have seen all of them with the NS query, you can now probe each individually.

nslookup domainname.com ns1.domainname.com

Change ns1.domainname.com with one of the name servers for your domain.

Check an IP address (Reverse DNS lookup)

You can also probe an IP address and see if there is a PTR record set in a Reverse DNS zone.

nslookup 111.111.111.111

Change the 111.111.111.111 IP address with the one you want to verify. It can be IPv4 or IPv6 address.

Learn more about rDNS

Nslookup check of a particular port for communication.

You can also use the NSlookup to check a server through a particular port. In this case, we will use port 53. Change it with another if you like.

nslookup -port=53 domainname.com

Give a particular time limit to wait for the response.

You can set the waiting period, in seconds, for the queries. Let’s set it to 35 seconds in this example. You can set it to another period.

Nslookup -timeout=20 domainname.com

Nslookup debug mode enable

nslookup -debug domainname.com

Conclusion

The NSlookup command is a very used tool because it is easy to find on different devices and works the same. It doesn’t have so much different behavior on the different Oses like some other network tools.

The Nslookup command can help you check your domain name and see problems with your DNS.

Error 502 Bad Gateway – 5 quick fixes

By Bob on August 9, 2021

What does Error 502 Bad Gateway mean?

Error 502 Bad Gateway is a HTTP status code. It is a general pointer that there’s something that is not right with a website’s server communication.

This status code shows that the server, while serving as a gateway or proxy, received an invalid response from an inbound server it accessed while trying to achieve the request.

If you want to visit a website on the Internet, your browser sends a request to a server connected to the web. This server receives the request and applies a process to deliver back the resources you demanded, including an HTTP header and an HTTP status code.

In case everything works, users are not going to see the HTTP status code. Simply, this is the way servers interact with each other. However, if something fails, the server will inform you with exactly this code.

Error 502 Bad Gateway can be displayed like:

502 Bad Gateway
Temporary Error (502)
HTTP 502
502 Proxy Error
502 Service Temporarily Overloaded
502 Server Error: The server faced a temporary error and is not able to complete your request.
Bad Gateway: The proxy server got an invalid response from an upstream server.

Let’s observe some of the quick fixes that could help you.

Reload the page.

The first thing you could try when you face an Error 502 Bad Gateway is simply to wait a moment and reload the page. Of course, the host or the server could be just overloaded. If it is so, the website should come right back.

Also, another thing to quickly try is opening the website through a different browser.

You can find platforms that can check if the website is actually down or the problem is on your side.

Remove Your Browser Cache

If the error continues, it could be the possibility that your browser cache holds outdated and corrupted data. If this is the case, you should clean the browser cache to fix this error.

It is important to know that removing the cache might lead to losing some essential browser data or bookmarks and preferences, which you set. Therefore, you should export your data from the browser, and after you finish removing the cache, import it back to prevent losing data.

Check for any DNS changes.

A possible reason for facing Error 502 Bad Gateway could be a DNS issue. For example, the domain does not reveal the right IP.

It is necessary to be patient for things to completely propagate, in case you recently migrated your website to a new host. The required time depends on the TTL value of your DNS records.

Briefly Disable Firewall or CDN

Perhaps there could be an issue with your firewall or Content Delivery Network (CDN). In case you are using a provider of CDN, you can simply disable your CDN for a moment. Then you can test to reach your website again.

This error is possible to occur sometimes with providers of DDoS protection and mitigation or fully proxy services. This is because they hold an extra firewall in-between. It can often happen if you are using a free plan.

Suggested article: Error 404 – how to fix it?

Reach your host.

In case you can’t solve the problem on your own, give a call to your host company. They can observe what is going on and deliver more information about the situation.

Perhaps the issue could be on their end, and they could be able to fix it easily. They can also help if the problem is particularly associated with your website.

Premium DNS service explained.

By Bob on July 6, 2021

If you are wondering what Premium DNS service has to offer and what is the purpose of DNS. Let’s make things a little bit more clear and dig a bit deeper into this topic!

DNS explained

It is important to mention what DNS is for the purpose of explaining Premium DNS accurately.

Domain Name System (DNS) is a global network of name servers. Its purpose is to indicate where domain names are. It links the domain names to their IP addresses. Also, the Domain Name System has features such as linking hostnames to other hostnames, further instructions about services, verifications, etc.

DNS is a communication network, which will guide all of your users to the correct addresses or other hostnames.

Premium DNS

Premium DNS is a DNS hosting provider’s service. In Premium plans, you can benefit from more of everything. You can take advantage from more DNS servers and DNS zones. Also, you are capable of managing the traffic better. If you choose the Premium DNS plan, you will see improvement in the loading speed for sure. It will provide better up time, better security, and even better SEO.

For companies that can’t afford to have downtime, Premium DNS is the service that should be implemented. Any website that is more than a small blog could benefit from Premium DNS

If the number of monthly visitors is increasing, you may need to consider using this service.

Here are some questions that can help you clarify if you need Premium DNS:

What is the number of people that need to connect to the site?
How often will these people connect?
Are all of these people only from your country? Or maybe there is an international interest in your site?
Do you require any extra security features? How critical is it for you to protect your customers at every move of their website journey?

Premium DNS advantages

Premium DNS gives you a solid foundation with the needed resources. Here is a general summary of the features Premium DNS providers can offer.

Many more DNS zones.
Ensured uptime.
Higher speed.
Robust DNS servers’ networks. Benefit from more presence points (PoP) for your company.
Implementing load balancing methods, including GeoDNS
Loading time is a lot faster.
Millions of queries, and often infinite amount.
Monitoring and checkings. DNSSEC support, cryptographic, and more high-level tech security to keep your site protected from attacks. Depending on the plan you picked, you can receive more or less features.
Efficient traffic management.
DNS Failover.
Many email forwards.
Friendly interface.
24/7 Professional support.

Conclusion.

Take your time when you are checking providers. What they guarantee and offer, and the costs. Premium DNS benefits must provide reliability and powerful performance. It is essential for demanding websites, such as government, banking, e-commerce, etc.

If your site is becoming bigger or has customers from around the globe, or you want to guarantee excellent security. That is the moment to begin using a Premium DNS service. It will increase speed, performance, redundancy, and security.