Dig command: How to use it in Linux?

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What does the Dig command do?

Domain Information Groper, or DIG for short, is a wonderful command-line utility. To provide comprehensive details on mail exchanges, host addresses, and other relevant information, we use Dig to query the DNS name server. This utility is compatible with a variety of operating systems, including Linux and macOS.

You can do DNS queries using the built-in Linux Dig command by using the Terminal application. Your domain can be troubleshot, and you can learn a lot of details about it, such as DNS records, Name servers, and general network information. Its excellent features include having more functionality than some built-in utilities, like nslookup, and being quite simple to use. Because of this, despite having a straightforward command-line interface, many network administrators use it often.

The most popular examples of the Dig command!

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Introduction to DNSSEC: Securing Your DNS Infrastructure in Linux

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The Domain Name System (DNS) is a foundational component of the internet, responsible for translating domain names into IP addresses. Despite its critical role, DNS was not designed with security in mind, making it vulnerable to a variety of attacks, including cache poisoning and spoofing. This is where DNSSEC (DNS Security Extensions) comes into play. DNSSEC is a suite of extensions that adds a layer of security to DNS by enabling authentication of DNS responses, protecting users and services from malicious redirection.

In this detailed technical blog post, we will explore the importance of DNS Security Extensions, how it works, and provide a step-by-step guide to securing your DNS infrastructure on Linux using DNSSEC.

What is DNSSEC?

DNSSEC (Domain Name System Security Extensions) is a protocol that enhances DNS by adding cryptographic signatures to DNS records. These signatures allow DNS resolvers (the systems responsible for querying DNS records on behalf of users) to verify the authenticity of the responses they receive from DNS servers.

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Troubleshooting Common DNS Issues in Linux

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Dealing with DNS issues can be frustrating, especially if you’re new to Linux. DNS is critical because it translates domain names like www.example.com into IP addresses that computers can understand. When DNS doesn’t work correctly, websites may not load, and you may have trouble accessing network resources. This guide will walk you through some common DNS issues in Linux and how to troubleshoot them effectively.

What is DNS, and Why Is It Important?

DNS (Domain Name System )is like a phonebook for the internet. It translates human-friendly website names into numerical IP addresses that computers use to find and load those websites. Without DNS, browsing the internet would require you to remember long strings of numbers instead of simple names.

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A Guide to Using Cron Jobs for Task Automation in Linux

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Automation is a key element in managing and optimizing systems, particularly in the Linux environment. One of the most powerful tools for task automation in Linux is the cron job. Cron jobs are scheduled tasks that run automatically at specified intervals, making them perfect for routine maintenance, backups, system monitoring, and much more. This guide will walk you through the basics of setting up and managing cron jobs, as well as monitoring their performance to ensure they run smoothly.

What is a Cron Job?

A cron job is a scheduled task that runs at regular intervals on Unix-like operating systems. The cron daemon (crond) is the background service that enables this functionality. Users can specify the timing and frequency of tasks using a syntax called a “cron expression”.

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How to Set Up SSH for Remote Access in Linux

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Secure Shell (SSH) is a powerful tool that allows you to access and manage your Linux system remotely over a secure network. Whether you’re managing a server or just want to access your home computer while you’re away, SSH is an essential skill to have in your toolkit. In this guide, we’ll walk you through the steps to set up Secure Shell for remote access in Linux.

What is SSH?

SSH, or Secure Shell, is a protocol that provides a secure channel over an unsecured network by using encryption. It allows you to log into another computer over a network, execute commands, and transfer files. Secure Shell is commonly used for remote server management.

How does SSH work?

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The MTR command – A Linux network diagnostic tool

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In the world of network administration, especially within Linux environments, having the right tools to diagnose and resolve network issues is essential. One such powerful tool that combines the capabilities of both traceroute and ping is the MTR command. MTR stands for “My Traceroute,” and it is instrumental in providing real-time data about network connections. In this blog post, we’ll explore what MTR is, how it works, and how you can use it to troubleshoot network problems.

What is the MTR command?

MTR is a network diagnostic tool that merges the functionality of the ‘traceroute’ and ‘ping’ programs into one integrated tool. By continuously sending packets to a specified destination, MTR collects real-time data about each hop along the route to that destination. This approach allows network administrators to monitor the network and identify issues more efficiently.

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IPv4 for beginners: All you need to know

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At the heart of Internet system lies IPv4, a fundamental component that facilitates the exchange of data packets across networks worldwide. But what exactly it is, and why is it so essential to the functioning of the modern internet?

What is IPv4?

IPv4, or Internet Protocol version 4, is a foundational protocol used for identifying and routing data packets across networks. It assigns a unique numerical label, known as an IP address, to each device connected to a network. These IP addresses serve as virtual addresses, enabling devices to locate and communicate with one another on the internet.

An IPv4 address consists of a 32-bit binary number, typically represented in decimal format for human readability. The decimal representation is divided into four 8-bit segments, known as octets, separated by periods. For example, an IPv4 address might appear as “192.168.1.1”.

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How can I clear (flush) my DNS cache in Linux?

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The Domain Name System (DNS) translates user-friendly domain names into the numerical IP addresses that computers understand. This translation process is expedited by the DNS cache, a local repository storing recent domain name lookups. While this cache enhances online efficiency, there are instances when its clearance becomes necessary. So, today, we will explain what it is and how to flush it in Linux systems and guide you through the process.

What is DNS Cache?

The Domain Name System (DNS) is a fundamental component of the internet, responsible for translating human-readable domain names into IP addresses that computers use to locate and communicate with each other. To expedite this process and reduce the time it takes to access websites or other online resources, operating systems and web browsers often maintain a local DNS cache.

In simple terms, a DNS cache stores recent DNS lookups, including the corresponding IP addresses. This means that when you visit a website, your computer doesn’t need to perform a full DNS lookup every time, which can improve page loading times. Instead, it can quickly retrieve the IP address from the cache. However, there are times when you might want to clear or flush it.

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​Linux, the object of the DNS cache poisoning attack

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In 2020, researchers from the University of California and Tsinghua University found a new method to execute DNS cache poisoning attacks. Unfortunately, Linux, a very reliable OS, was the object of the DNS cache poisoning attack.

​What is DNS cache poisoning?

A DNS cache poisoning (DNS spoofing) is a cyberattack that pollutes the cache on DNS resolver servers. This can cause the user to be redirected to the attacker’s server instead of the right one.

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How to use the Traceroute command?

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Are you a network administrator and want to gain insight into your network’s traffic? Then, the Traceroute command is here to your rescue! This simple yet powerful network diagnosis tool measures the latency of a connection to a given destination and provides a complete route path and associated latency. In this blog post, we’ll deeply dive into the Traceroute command and discuss how to use it, why to use it, and its benefits. So let’s get started and learn more about this invaluable networking tool!

What is the Traceroute command?

The Traceroute command is a powerful network diagnostic tool used to measure a connection’s latency to a given destination. When executed, this command sends a series of ICMP packets to the target, each with an increasing TTL value. As the responses are returned from each hop in the route to the destination, the Traceroute command can display the route path and associated latency. It can help network administrators find latency issues, track down errors, and understand the route path between two points. It is a valuable tool for troubleshooting and understanding networks.

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​How to check DNS records on Windows, Linux and macOS?

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Being an online business owner or a network administrator, checking DNS records will become a constant task for you. So better to know how to do it from now!

​How to check DNS records on Windows, Linux and macOS? 

To check DNS records on Windows, Linux, and macOS, you can use the nslookup command. This command allows you to query DNS servers for information about a specific domain or hostname. Linux and macOS have another choice to check DNS records which is the host command. Both “nslookup” and “host” work well, but the second provides more detailed statistics and more options for precise searches. We do recommend using the host command!

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