Linux

Single sign-on (SSO) is a vital cloud security technology that reduces all user application logins to one login for greater security and convenience. What is single sign-on (SSO)? Single sign-on (SSO) is a technology that combines several different application login screens into one. With SSO, users only have to enter their login credentials (username, password, … Read more

Virtual machines (VMs) are computers that run inside of other computers using a process known as virtualization. What is a virtual machine? A virtual machine (VM) is a software-based computer within another computer’s operating system, often used for testing, backing up data, or running SaaS applications. To grasp how VMs work, it’s essential to understand … Read more

Client-side and server-side are web development terms that describe where application code runs. Web developers will also refer to this distinction as the frontend vs. the backend, although client-side/server-side and frontend/backend aren’t quite the same. In a serverless architecture, the serverless vendor hosts and assigns resources to all server-side processes, and the processes scale up as … Read more

“The power of sudo is strong with this one!” Sudo is a command-line utility for Unix and Unix-based operating systems such as Linux and macOS. The utility provides an efficient way to temporarily grant users or user groups privileged access to system resources to run commands they cannot run under their regular accounts. Users can … Read more

Host command is a minimal and easy-to-use the command line interface, or CLI utility for performing DNS lookups which translate domain names to IP addresses and vice versa. It can also be used to list and verify various types of DNS records such as NS and MX, test and validate ISP DNS server and Internet … Read more

nslookup is a command-line administrative tool for testing and troubleshooting DNS servers (Domain Name Server). It is used to query specific DNS resource records (RR) as well. Most operating systems come with a built-in nslookup feature. This article demonstrates the widely used nslookup command in detail. Nslookup can be run in two modes: Interactive and … Read more

In this article, you will learn how to install the dig command and nslookup command on Linux. These commands are used for network troubleshooting and gathering information about domain names. Dig, short for Domain Information Gopher, is a DNS lookup utility used for probing DNS servers and troubleshooting problems associated with DNS servers. Due to … Read more

In our previous article, we have explained nslookup command examples and usage, which is a networking command-line tool used for querying and getting information of DNS (Domain Name System). Here, in this article, we come up with another command line tool called dig, which is much similar to the Linux nslookup tool. We will see … Read more

Sometimes your Linux distribution doesn’t detect your laptop’s Bluetooth hardware. Or perhaps you want to add a USB Bluetooth dongle to a desktop computer. Either way, here’s how to get Bluetooth working. Bluetooth is named after a 10th-century Danish king, Harald Bluetooth. He was known as the unifying king. By encouraging communication between the many … Read more

Feel like starting over? This tutorial will show you how to cleanly and safely reboot or shut down your Linux or macOS computer from the command line. We’re Going Down Sometimes you just have to go for the reboot or the total shutdown. If you’re working on a GUI-less server or you’re on an SSH … Read more

The Linux File System – Explained

Kali Linux is an open-source, Debian-based Linux distribution geared towards various information security tasks, such as Penetration Testing, Security Research, Computer Forensics, and Reverse Engineering. This niche prefers that distro; these tools could be manually installed on other Linux Distros, maybe even Windows ports. However, Kali and Parrot Linux are the more popular Linux Distros … Read more

If you want to cause chaos in a Linux environment, put this in the ~/.bash_aliasis file… PURE EVIL. Caution, do not try this at home kids!

When we refer to access control systems, we’re talking about providing access to restricted areas of the enterprise. But familiarity and correctly utilizing access control systems to protect proprietary information are two completely different levels of understanding. For example, who gets access to what? What are the rules? How is access tracked? The user must first be … Read more

Digital transformation, regardless of whether a private venture or a large organization, has empowered companies to produce information at every touchpoint. Irrespective of the organization, each organization requires a database to sort out and store its fundamental data. To provide such a facility, the database management system software is to the rescue. A database can be referred … Read more

Cryptography studies secure communications techniques that allow only the sender and intended recipient of a message to view its contents. The term is derived from the Greek word “kryptos”, which means hidden. It is closely associated with encryption, which is scrambling ordinary text into what’s known as ciphertext and then back again upon arrival. In addition, cryptography … Read more

You don’t remember individual mobile numbers. Instead, you go to your contacts app and call it by their names. The contacts app allows people to input everyday words without having to keep track of the individual mole number. This is the exact same thing DNS does for the internet. Domain Name System Computers address each … Read more

Do you have a Windows 11 computer or device and don’t know how to access the UEFI or BIOS? Are there any issues with your PC that you think can be repaired from there? Whether you need to enter UEFI/BIOS to troubleshoot your computer or adjust settings to improve its performance, in this tutorial, we … Read more

CONTENTS If you are a casual computer user, you may have heard about the BIOS, UEFI BIOS, BIOS failures, or Dual BIOS motherboards, but you might be wondering what these terms mean. What is a BIOS except for a weird-sounding acronym? What does BIOS do? Is it that important for the operation of a computer? … Read more

When administering MySQL database servers, one of the most common tasks you’ll have to do is to get familiar with the environment. This involves tasks such as listing databases that reside on the server, displaying the tables of a particular database, or getting information about user accounts and their privileges. This tutorial explains how to show all databases in … Read more

MySQL is the most popular open-source relational database management system. MySQL server allows us to create numerous users and databases and grant appropriate privileges so that the users can access and manage databases. This tutorial explains using the command line to create and manage MySQL or MariaDB databases and users. Before you begin Before starting … Read more

Typically when you run a command in the terminal, you have to wait until the command finishes before you can enter another one. This is called running the command in the foreground or foreground process. When a process runs in the foreground, it occupies your shell, and you can interact with it using the input … Read more

MySQL is the most popular open-source relational database management system. This tutorial explains how to create MySQL or MariaDB databases through the command line. Before you begin We are assuming that you already have MySQL or MariaDB server installed on your system. All commands are executed as an administrative user (the minimum privilege required to create a new … Read more

MySQL is the most popular open-source relational database management system. This tutorial describes how to delete (or drop) a MySQL or MariaDB database through the command line. Before you begin All commands are executed as an administrative user (the minimum privilege required to delete a database is DROP) or with a root account. To access the MySQL console type … Read more

MySQL is the most popular open-source relational database management system. MySQL server allows us to create numerous user accounts and grant appropriate privileges so that the users can access and manage databases. This tutorial describes how to create MySQL user accounts and grant privileges. Before you Begin We assume you already have MySQL or MariaDB … Read more

MySQL allows you to create multiple user accounts and grant appropriate privileges so that the users can connect and manage databases. If the user account is no longer needed, it is a good idea to either remove the user privileges or to completely delete the user account. This tutorial explains how to delete MySQL/MariaDB user accounts. DROP … Read more

In this tutorial, we will show you how to change MySQL user passwords. The instructions should work with any modern Linux distribution such as Ubuntu 18.04 and CentOS 7. Prerequisites Depending on the MySQL or MariaDB server version you are running on your system, you will need to use different commands to change the user … Read more

Have you forgotten your MySQL root password? Don’t worry, it happens to all of us. In this article, we will show you how to reset the MySQL root password from the command line. Identify the Server Version Depending on the MySQL or MariaDB server version you are running on your system, you will need to … Read more

Have you ever needed to get a list of all users in your MySQL server? There are commands to show databases and tables, but there is no MySQL show users command. This tutorial explains how to list all user accounts in a MySQL database server through the command line. We’ll also show you how the find out … Read more

GDU Disk Usage Analyzer is a graphical disk usage analyzer for GNOME. It was part of gnome-utils but was split off for GNOME 3.4. It was originally named Baobab after the Adansonia tree. The software gives the user a menu-driven, graphical representation of what is on a disk drive. GDU is inspired by godu, dua, ncdu, and df and is intended primarily for … Read more

Contents: Option 1: Display the Size of a Directory Using the du Command Option 2: Get Size of Directory in Linux Using tree Command Option 3: Find the Size of a Linux Directory Using ncdu Command Introduction Many users run Linux from the command line. However, the command line – sometimes known as the terminal … Read more

Introduction How much space do I have free on my Linux drive? Managing disk space on a Linux server is an important task. For example, package manager applications notify you of how much disk space will be required for an installation. For that information to be meaningful, you should know how much space your system has available. … Read more

Prerequisites Step 1 — Installing Apache and Updating the Firewall How To Find your Server’s Public IP Address Step 2 — Installing MySQL Step 3 — Installing PHP Step 4 — Creating a Virtual Host for your Website A Note About DirectoryIndex on Apache Step 5 — Testing PHP Processing on your Web Server Step … Read more

Introduction Sudo is SuperUser DO and is used to access restricted files and operations. By default, Linux restricts access to certain system parts, preventing sensitive files from being compromised. The sudo command temporarily elevates privileges allowing users to complete sensitive tasks without logging in as the root user. In this tutorial, learn how to use the sudo command in Linux with … Read more

Log files are an essential part of Linux system administration and monitoring. But log files also quickly grow and take up a lot of storage space. The good news is that a tool called Logrotate in Linux lets you manage log files effectively. In this tutorial, you’ll learn how to configure Logrotate so you can manage and … Read more

ping (Packet Internet Gropper) The Ping command allows a user to ping another network IP address. Ping command sends ICMP ECHO_REQUEST packets to other hosts, and this command can help determine the connectivity to the remote host. This is similar to playing “Marco Polo” in a body of water. Simple ping command syntax is ping … Read more

I’ll compare the Norton 360 Deluxe plan, their second most expensive, to Bitdefender’s most expensive Total Security plan. Why do you ask? Because they both claim to offer the same level of protection and supplemental features, by and large, they’re almost identical packages…or so I thought… 🔥 Bitdefender vs. Norton: Malware protection: 🔥 Now, starting … Read more

plipconfig – fine-tune PLIP device parameters SYNOPSIS plipconfig interfaceplipconfig interface [nibble NN] [trigger NN] [unit NN] DESCRIPTION Plipconfig is used to (hopefully) improve PLIP performance by changing the default timing parameters used by the PLIP protocol. Results are dependent on the parallel port hardware, cable, and the CPU speed of each machine on each end of … Read more

DISCLAIMER I’m not a certified financial planner/advisor nor a certified financial analyst nor an economist nor a CPA nor an accountant or a lawyer. I’m not a finance professional through formal education. I am just a hacker. I am unsure of my reboot scripts at this moment, or if the new XMR / Monero miner, MoneroOcean.stream’s new … Read more

Ssh is a secure protocol used to manage remote systems like Linux, BSD, UNIX, network devices event windows operating systems. The traffic between systems is encrypted. Ssh uses asymmetric keys in order to encrypt and make traffic invisible to the others who reside between systems in the network. The encryption power comes from key bit … Read more

I recently read that SSH keys provide a secure way of logging into a Linux and Unix-based server. How do I set up SSH keys on a Linux or Unix-based system? In SSH for Linux/Unix, how do I set up public-key authentication? This page explains a public key and shows you how to set up … Read more

Table of Contents The Objective The purpose of this post is to explain with an example how ansible initiates the reboot and waits for the reboot to complete. In some cases, we want our remote nodes to be rebooted or restarted. For example, Take Patching as an example. As part of quarterly patching, we upgrade … Read more

There are several ways to check the availability of a file in Linux. The “test” command in bash scripting is one of the critical approaches to checking a file’s existence. The focus of this guide is to discuss the presence of a file in your system through bash scripting: How to check file existence using … Read more

Indeed to reboot the VM or bare metal Linux machine/server using Ansible and wait for it to come back but it does not work with the playbook as described here. How to reboot the Linux server with Ansible? How do I reboot and wait for the reboot to complete in the Ansible playbook for multiple … Read more

If you’re troubleshooting a service that you know is running normally, the next step is to ensure it’s listening on the correct network port. The netstat command shows the services listening to ports on a Linux server and the details of any connections currently made to them. During basic network daemon troubleshooting, the connection details … Read more

The vi and vim editors allow you to copy text from your file into temporary buffers for use in other places in the file during your current vi work session. Each buffer acts like temporary memory, or, as some programs call it, a “clipboard” where you can temporarily store information. The simplest case would be … Read more

I recently added some extra repositories with the Mysterium network and received this error when I reloaded the apt package database: To fix this, I found to execute the following commands in the terminal: sudo apt-key adv –keyserver keyserver.ubuntu.com –recv-keys <PUBKEY> sudo apt-key adv –keyserver keyserver.ubuntu.com –recv-keys ECCB6A56B22C536D Then Update the apt cache: ALTERNATE METHOD: … Read more

All the Linux distributions are either derivatives of GNU/Linux ( OS made up of Linux Kernel developed by Linus Torvalds and GNU software repository) or derived from other Linux derivatives. This post will review the top 12 most popular Linux distributions based on the usage statistics and market share. DistroWatch has been the most reliable source … Read more

CentOS 8 Early EOL in 2021 and CentOS Stream The CentOS 8 life cycle has been cut short with the news of its EOL in December 2021. RHEL revealed it would be shifting focus from CentOS Linux to CentOS Stream. Most CentOS users who have updated their systems to the latest version have already expressed their concerns. While CentOS … Read more

Here, we will compare these two protocols’ main characteristics, and we will look at TCP Protocol (Transmission Control Protocol) and UDP Protocol (User Datagram Protocol). This comparison is very important and, generally, a question asked in Network Engineering, Cyber Security, or Infrastructure interviews. It also is important for students and security certification tets and is a simple … Read more

Proxy chains are open source software for Linux systems and come pre-installed with Kali Linux, the tool redirects TCP connections through proxies like TOR, SOCKS, and HTTP (S), allowing us to chain proxy servers. With proxy chains, we can hide the IP address of the source traffic and evade IDS and firewalls. We can use … Read more

Introduction Ubuntu 20.04 (codenamed Focal Fossa) was released on April 23, 2020. It is a Long-Term Support (LTS) release, which will receive support and updates until April 2025. This guide will help install a fresh copy of Ubuntu 20.04 LTS on your computer. Prerequisites System requirements (recommended): 2 GHz dual-core processor 4GB memory 25GB available disk … Read more

Setting up cron jobs in Unix, Solaris & Linux Cron is a Unix, Solaris, Linux utility that allows tasks to be automatically run in the background at regular intervals by the cron daemon.  Cron meaning – There is no definitive explanation, but the most accepted answer is reportedly from Ken Thompson ( author of Unix cron … Read more

How do you remove a password from a .key file using OpenSSL. You will be prompted for your original password, so enter that first then the new key will be written afterwards. Note you could have the -in and -out parameters be the same but if you get it wrong you could mess up your … Read more

Using the passwd command, you can change a user’s password and settings related to password expiry. There are two possible ways to achieve this, as described in detail, below. Using passwd Command To force a user to change his/her password, first of all the password must have expired and to cause a user’s password to expire, you … Read more

In this tutorial, you will learn: The default Ubuntu firewall is ufw, with is short for “uncomplicated firewall.” Ufw is a frontend for the typical Linux iptables commands, but it is developed in such a way that basic firewall tasks can be performed without the knowledge of iptables. Additionally, ufw can be managed from a graphical interface, gufw. … Read more

SSH is the most secure means of connecting to Linux servers remotely. And one of the common errors encountered while using SSH is the “ssh: connect to host port 22: No route to host”. In this short article, we will show how to troubleshoot and fix this error. Here is a screenshot of the error we … Read more

How does it work? Netplan reads network configurations from /etc/netplan/*.yaml, written by administrators, installers, cloud image instantiations, or other OS deployments. During early boot, Netplan generates backend-specific configuration files in /run to hand off control of devices to a particular networking daemon. Netplan currently works with these supported renderers. Software requirements and conventions used Category Requirements, Conventions or Software … Read more

Package Description The NET-3 networking toolkit Quick Install Instructions of net-tools on Ubuntu Server. It’s Super Easy! Simply Copy (CTL-C) to copy the command and paste (CTL-V) it into your command line terminal using the built-in APT package manager. You will need admin rights to install this like almost anything when you use apt or apt-get (yum but that’s … Read more

What if you had to memorize the IP address of every website that you wanted to visit? I bet you’d go crazy in no time! This is where DNS jumps into the scene. The Domain Name System has revolutionized the Internet. In this article, I’m going to discuss what a DNS actually is and how it works. … Read more

The ‘/etc/fstab’ file is one of the important configuration file used by Linux machines which specify the devices and partitions available and where/how to use these partitions. This file will be created/updated during the system installation. You need to modify or maintain it in the way you need to use the devices/partitions. In Linux each … Read more

The simple stuff Depending on whether you want to add ~/opt/bin at the end (to be searched after all other directories, in case there is a program by the same name in multiple directories) or at the beginning (to be searched before all other directories). You can add multiple entries at the same time. PATH=$PATH:~/opt/bin:~/opt/node/bin or variations on the … Read more

The shell can be defined as a command interpreter within an operating system like Linux/GNU or Unix. It is a program that runs other programs. The shell facilitates every computer user as an interface to the Unix/GNU Linux system. Hence, the user can execute different tools/utilities or commands with a few input data. The shell … Read more