Crontab Introduction

A daemon’s name is Cron. Daemons are utility programs in Linux that operate in the background, monitoring and carrying out activities in response to triggering events and programmed schedules. Daemons can also be used to automate repetitive tasks.

The origin of the term “cron” can be traced back to the Greek word “Chronos,” which can be translated as “time.” Cron is a daemon that operates according to a set timetable or calendar, as this indicates.

A long-running piece of software known as the cron daemon is a system tool responsible for executing commands at specific dates and times. When using cron daemons, you can schedule computer activities as one-time events, occasional events, or as jobs that are scheduled repeatedly and on a regular basis.

Cron scheduling is useful for many businesses because it can automate repetitive operations, edit databases, data, or files, send bulk email messages, and conduct administrative tasks on a predetermined schedule.

The scheduling syntax that cron utilizes is also often used by software that does not run on operating systems. An example is Zuar’s Mitto data pipeline solution. Mitto can automate a wide range of processes by utilizing cron scheduling, including manipulating data within data warehouses, pulling data from other software, and many more.

The term ‘Cron Table’ can be abbreviated to ‘Crontab,’ a component of Cron. It is a file containing the cron schedule that needs to be executed and the commands used to automate operations and activities. When you make a new cron job, its information will be saved in the crontab file.
System administrators can only modify the system crontab file. However, many administrators are supported by Unix-like operating systems. Everybody can make a crontab file and add commands to it anytime.

Users may automate system upkeep, disk space monitoring, and backup scheduling with cron jobs. Cron jobs are ideal for servers and other machines that operate continuously because of their nature.

Cron jobs can be useful for web developers even though system administrators often utilize them.

As a website administrator, you could, for instance, set up three cron jobs: one to check for broken links every Monday at midnight, one to back up your site every day at midnight automatically, and one to delete the cache of your site every Friday at noon. (more…)

Introduction

The issue of privacy is becoming more and more controversial. Users of Linux can encrypt files with public-key cryptography by using the gpg command. If you were to lose your encryption keys, this would be a disastrous situation. This is how you may support their claims.

OpenPGP and GNU Privacy Guard

One benefit of electronic files over paper hard copies is the ability to encrypt them so that only authorized users may access them. It won’t matter if they end up in the wrong hands. The contents of the files are only accessible to you and the intended recipient.

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Introduction

In UNIX/Linux-based systems, Monit is a free, open-source tool that automatically manages processes, files, directories, checksums, permissions, filesystems, and services like Apache, Nginx, MySQL, FTP, SSH, SMTP, and others. It also gives system administrators excellent and practical monitoring functionality.

A native HTTP(S) web server or the command line interface can be used to immediately view the system status and setup procedures via the monit’s user-friendly web interfaces web server, such as Apache or Nginx, must be installed on your system in order to access and view the Monit web interface. (more…)

What is s-tui?

“s-tui” is a terminal utility that runs GNU/Linux and is made to stress test and monitor our CPU. It is a program that graphically displays the frequency of CPU temperature utilization and power consumption without needing an X server. It was created by Alex Manuskin and is written in Python.

An effective way to determine whether a cooling system is working well or whether we have a stable overclock is to run a stress test on a computer. S-tui makes it simple to identify overheating when you see a decrease in frequency. Additionally, it will display any signs of decreased performance.

We can use the tool over SSH because it operates in the terminal. This is helpful if you enjoy using the terminal or for monitoring servers or small PCs like Raspberry Pi.

S-tui does not display precise information about the active processes in the system, which is one drawback of this tool. Just imagine the overall scene. S-tui won’t be of assistance if we’re searching for a tool that provides us with details about specific processes or allows us to manage these processes.

Install s-tui on Ubuntu using the PPA

The installer can also be downloaded and installed for Ubuntu systems using pip or a PPA. We merely need to launch a terminal (Ctrl + Alt + T) and enter the following commands to install s-tui from the PPA:

sudo add-apt-repository ppa:amanusk/python-s-tui && sudo apt update && sudo apt install python-s-tui

To start the program, we need to type “s-tui” in the terminal.

By adding stress, we can expand the program’s alternatives. This package allows us to run the stress test. Although installing this program is not required, it performs excellently. To accomplish this, using the terminal, we type:

sudo apt install stress

Archlinux users:

Use the Pacman command to install the pip package for Archlinux users.

sudo pacman -S python-pip stress

Fedora users:

sudo dnf install python-pip stress

For CentOS/RHEL users:

sudo yum install python-pip stress

For openSUSE users:

sudo zypper install python-pip stress

Stress can be used to highlight the CPU. All the graphs will advance to their maximum values if we choose this mode of operation.
Finally, use the pip command below to install the s-tui utility on Linux:

For Python 2.x:

sudo pip install s-tui

For Python 3.x:

sudo pip3 install s-tui

Getting to S-TUI

The article’s introduction stated as much. To obtain all the information from your system, root privilege is required. To start s-tui, simply enter the following command.

sudo s-tui

By default, it activates hardware monitoring and chooses the “Stress” option to put your system through a stress test.
Go to the help page to see alternative possibilities.

s-tui --help

Introduction

Typically, SSH-enabled servers make for easy targets for brute-force attacks. The ongoing development further increases the risk of intrusion by hackers of new software tools and bots for automating brute-force attacks.

This manual will look at strategies to protect your SSH servers from brute-force attacks on Linux distributions based on RHEL and Debian derivatives.

1. Disable SSH Password Authentication and Enable SSH-Key Authentication

Username/password authentication is the standard authentication technique for SSH. But as we have seen, brute-force attacks can be used to target password authentication systems. Implementing key-based SSH authentication, in which authentication is made possible via public and private SSH key pairs, is advised to be safe. While the public key is copied to the server, the client’s private key stays on their computer.

During SSH key authentication, the server verifies whether the client PC has the private key. A shell session is created, or the command supplied to the remote server is executed if the check is successful. You may find detailed instructions for configuring SSH key-based authentication on our website. (more…)

Introduction

MySQL is an open-source relational database that many users prefer to use in their daily operations because of the diversity of storage engines it supports, its flexibility and high performance, robust data security, cost-effectiveness, ease of maintenance, and reliability.

Why should MySQL performance be measured and monitored?

Ensuring smooth and effective database performance is one of the most important features of any organization or company, large or small. Thus, in some cases, having a complete understanding of database uptime or load is crucial and should be monitored frequently.

As a result, numerous monitoring tools are available on the market to track, analyze, and measure performance, as well as examine potential difficulties. They help you optimize queries and visualize database metrics, collect statistics, and present the performance status so that you can understand the influence on overall performance and potential issues that need to be troubleshot.
The following advantages may emerge from optimizing database performance: (more…)

Introduction

Have you ever worked away from home and realized that you left a critical document on your computer? The optimal method is to utilize an FTP server such as Very Secure FTP Daemon (VSFTPD).
You can install and configure an FTP server using VSFTPD on your Linux server by following the steps in this guide. With this server, you can safely transfer files to other computers.

Continue reading, and you’ll never have to worry about your files being held hostage on your home computer again!
The File Transfer Protocol, sometimes known as FTP, is a standard network protocol that sends and receives data to and from remote networks. Linux users have access to various open-source FTP servers to choose from. PureFTPd, ProFTPD, and vsftpd are the ones that have the most notoriety and are utilized the most frequently. We will install vsftpd (Very Secure FTP Daemon), a dependable, secure, and quick FTP server. In addition, we will demonstrate how to configure the server so that users can only access their home directories and the entire transmission is encrypted using SSL/TLS.

Although FTP is a highly used protocol, you should consider using SCP or SFTP instead if you want to transfer data in a more protected and expedient manner.
In this blog, we will use Ubuntu and similar Debian base distribution; however, any other Linux distribution should also work. (more…)

What is Cacti

The following features are offered by Cacti, a comprehensive network graphing solution created to maximize the potential of RRDtool’s data storage and graphing functionality:

• Remote and local data collectors
• gadget discovery
• generation of devices and graphs automatically
• Device and graph tagging
• individual data gathering techniques
• Controls over the user, group, and domain access

All of this is contained inside a simple interface that is both intuitive and easy to use and is appropriate for both small LAN installations and extensive networks with hundreds of connected devices.

Ian Berry created it as a high school project in the early 2000s. Hundreds of businesses and enthusiasts have used it to monitor and manage their enterprise networks and data centers.

Suppose you see any issues referencing missing tables or columns in the database, whether you are working with the source code or downloading the code directly from the repository. In that case, you must perform the database upgrade script. (more…)

Introduction

The components shown on a computer monitor are controlled by a specialized circuit board known as a video card. It is also known as a graphics processing unit or GPU and is responsible for calculating 3D visuals and pictures for use in Linux gaming and other applications. Let’s have a look at the best Linux command-line tools for GPU monitoring and diagnostics so we can fix this problem.
There is a possibility that a graphical processing unit (GPU), often called a video or graphics card, could be present on a Linux machine. Active graphics card monitoring and control can be necessary for various contexts, including mining cryptocurrencies, operating gaming servers, or improving the user experience on a desktop computer.

GPU monitoring and Diagnostic Tools

lshw -C display -short

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What Is Ncdu?

The name “NCurses Disk Usage” (or “Ncdu”) refers to a curses-based alternative to the well-known “du” command. It offers a quick method of determining which directories are taking up disk space.

The creator of the Ncdu software is not happy with all of the tools and methods available in Linux for analyzing disk utilization. Therefore, he used the C programming language and a ncurses interface to create Ncdu.

Ncdu is a straightforward and quick disk utilization analyzer used to determine which directories or files on local or distant computers are using up more space.

Without further ado, let’s get started learning how to install Ncdu in Linux and how to use it to check disk utilization in Unix-like operating systems like Linux.

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