Since Debian 10, the Debian Linux distribution uses systemd to control the starting and stopping of services, and Systemd also controls the whole boot and shutdown process of the operating system. The consequence of switching from init.d to Systemd is that some commands to stop or restart Debian, like 'shutdown -h now' or 'reboot' do ... Read more
Windows users are used to being able to create shortcuts to have fast access to their files and folders easily. This is especially useful when these are buried deep in their filesystem. This feature isn't as obvious on most Linux systems as it is on Windows. In this guide, I'll show you how to create ... Read more
This guide will show you step-by-step how to requeue emails in Postfix on Linux. I've been using these steps on my Debian and Ubuntu mail servers, but they should work on other Linux distributions like CentOS, Rocky Linux and AlmaLinux too. Requeue Email in Postfix Access the Linux System: Log in to the Linux system ... Read more
When working with any operating system, you often come across such situations when you want to capture the screen and capture screenshots on PC, also referred to as capture screen picture. Often, you may need high-quality screenshots. In this article, we will explain two methods for capturing good screenshots using a screenshot app with a ... Read more
Using the tcpserver program on Linux is not deprecated. Tcpserver is a utility included in the ucspi-tcp package that listens for connections from TCP clients and, for each connection, executes a specified program. This tool is particularly useful for setting up simple TCP services, where each incoming connection triggers the execution of a program, script, ... Read more
Using xinetd (Extended Internet Service Daemon) on Linux is not deprecated, but its usage and relevance have evolved over time. Xinetd is an open-source super-server daemon that runs on many Unix-like systems, managing Internet-based connectivity. It is a more secure and feature-rich alternative to the older inetd ("Internet daemon"), which has been deprecated by most ... Read more
In this example, I will use the getent command to check if a Linux group exists. if getent group "$groupname" >/dev/null; then echo "Group $groupname exists" fi Replace $groupname with the name of the group you want to check. If you like to check if the group does not exist (e.g. because you like to ... Read more
Here I will show you how to check if a Linux user exists (or does not exist) in a POSIX-compatible shell like Bash or Dash. I will use the getent command along with the /etc/passwd file for this. Example Bash script: if getent passwd "$username" >/dev/null; then echo "User $username exists" else echo "User $username ... Read more
The bash history is a log file that contains all commands that a user executed on the Linux BASH shell. When you use the "arrow up" key on your keyboard, then Bash will look up the previous command from that file and display it on the screen. You just have to press "Enter" to execute ... Read more
Bash shell refers to Bourne Again Shell which can be found as the default shell in most of the Linux distributions. A Bash Script is a file where multiple shell commands are scripted to perform a particular task. If you are familiar with bash script then this article is for you, in this demonstration I ... Read more