


Copying directories using SCP
SCP, or Secure Copy, is a command-line utility used to copy files and directories between two remote hosts over a secure SSH connection. It is a simple and secure way […]

Concatenating strings in Bash
Concatenating strings in Bash is a common task that you may come across when working on shell scripts. This article will guide you through various methods of concatenating strings in […]

Sort the list of file names using ls command
To list only the file names using ls command we can pass -a option to it. You can sort the file names by passing | sort to the ls -a […]

Kill all processes running on a port in Linux
To kill all processes running on the port 8080:

View processes list in tree format in Linux
pstree is a command that shows the running processes as a tree. It is used as a more visual alternative to the ps command. The root of the tree is […]

Get home directory of logged in user in Shell
Using a built-in variable: Using a tilde:

Get current user in Shell
Using a built-in variable: Using a command:

Get the number of processors in Linux and MacOS
This command queries the configured processor values using the getconf command. Example

unable to create listener: Error listen tcp4 0.0.0.0:443: bind: permission denied – Fix in Ubuntu
I was trying to use kubectl and port forward the service ports to local but Ubuntu doesn’t allow to bind to 443. To fix this we can use setcap and […]

Update Node.Js To latest version in Ubuntu
To know the current version of node.js / npm installed in your Ubuntu system, run the following command. To see the latest releases of npm: To install any version of […]

How to Install Kubectl in Ubuntu?
We are going to use the debian package managers to install Kubectl in Ubuntu. Output Output Output Output Output

Get OS version (32 bit or 64 bit) in Linux
To get OS version i.e 32 bit or 64 bit, just run the following command in terminal. This will return the number your processor is based on, 32-bit processor or […]

Update all packages in Ubuntu
Updating packages in Ubuntu is sometimes needed to upgrade your Ubuntu to latest version and apply security updates. We can also upgrade all packages in the system to make sure […]

Save server certificate to your local machine using bash
To save a server certificate to your local machine, we can use openssl and read from the https port 443 and save it using echo. Save the above script to […]

Challenge failed for domain – Certbot error – How to fix?
I was setting up letsencrypt certificates to enable SSL on one of my ubuntu servers. I mapped a domain (zumpdo.xyz) to my server, installed nginx and I ran the certbot […]

List processes using internet in Ubuntu
To list the processes that are using your internet connection in Ubuntu (or Linux, in general), we can use the netstat –inet -ap command. This command will list down the […]

How to attach to an existing tmux session?
To get the list of existing tmux session use tmux ls command. Here there is one session that already exists. To attach to this particular session ‘0’ we can use […]

Install Terraform in Ubuntu/Debian
In this post let’s discuss how to install Terraform in Ubuntu / Debian operating systems. HashiCorp is the company who develops and maintains Terraform packages. We can install Terraform using […]

Install KVM on Ubuntu 20.04
In this quick post we will focus on install KVM on Ubuntu 20.04. Kernel-based Virtual Machine (KVM) is an open source virtualization technology built into Linux operating systems. Ubuntu uses KVM as […]

How to install and init Google Cloud SDK in Linux (Debian / Ubuntu)?
In this post, we will learn how to install Google Cloud SDK in a Linux operating system especially Debian and Ubuntu distributions. Google Cloud SDK is a set of tools, including gcloud, […]

How to install Deno in Ubuntu?
In this tutorial we focus on how to install Deno in Ubuntu. Deno is a simple, modern and secure runtime for JavaScript and TypeScript that uses V8 and is built […]

Install Node.js and PM2 in CentOS 7
Learn how to install Node.js, npm and pm2 in CentOS 7. If you are using DigitalOcean droplet with CentOS Linux distribution, you might want to learn this. Install Node.js 12.x […]

Remove a user and group in linux (Centos / Ubuntu)
Learn how to remove a user in linux. Learn how to remove a group in linux. Removing a user in linux To remove a user, we use userdel command. Syntax […]

Create a new user and add to a group in CentOS / Ubuntu / Linuxmint
Learn how to create a new user and add the user to a group in CentOS / Ubuntu / Linuxmint distributions of Linux. Before you start creating users and groups, […]

Apache Error – Permission denied: AH00072: make_sock: could not bind to address – How to fix?
Find out how to fix the Apache error Permission denied: AH00072: make_sock: could not bind to address. First start the server with sudo and see if this error is gone. […]

Expose your local application as a public URL using ngrok
Learn how to expose your local application as a public URL using ngrok. You have developed an application and testing it in your local machine, but you want it to […]

Downloading files with cURL command
Find out how to download files using curl command in terminal. Curl command helps to access a URL directly from the command-line in Linux. cURL which stands for Client URL […]

Send cookie from one URL to the other using curl in Shell
In this post, we are writing about how to pass cookies from the response of one URL to the request of another URL. In some cases, when you are testing […]

Install Bugzilla on Centos 7
In this guide, we will show you how to install Bugzilla bug tracking system on CentOS 7 hosted on DigitalOcean or Alibaba Cloud or any other cloud engine. Upgrade your […]

How to kill a process in Linux?
Learn how to kill a running process in Linux using Kill, Pkill and Killall commands. These commands terminates processes abruptly and make sure the system continues to run. In Linux, […]

How to change Apache Httpd default port in Linux?
Find out how to change Apache Httpd default port in Linux from the default 80. I was working with Apache server and I used it as a web server for […]

Install Apache Server on CentOS 7
In this guide, we will show you how to install Apache httpd Server on CentOS 7 hosted on DigitalOcean or Alibaba Cloud or any other cloud server. Install Apache Server […]

Install MariaDB on CentOS 7
In this post, we’ll show you how to install MariaDB on a CentOS 7 instance hosted on DigitalOcean or Alibaba Cloud or any other cloud server. MariaDB is basically MySQL […]

Permissions are too open – SSH Error – How to fix?
Permissions are too open – SSH Error – How to fix? This error implies you have set the permissions on your hidden .ssh directory to be read by everyone. The […]

Install MongoDB in Ubuntu 18.04 and 19.04
The steps given in this post are tested on Ubuntu 19.04, however, they are the same for other Ubuntu versions such as 18.04, 16.04, 15.04, 14.04. If you want to skip […]

Add a custom screen resolution in Ubuntu 19.04
xrandr is a command-line tool to interact with the X RandR ((Resize and Rotate) extension, which allows for live (re)configuration of the X server (i.e. without restarting it): It provides […]

Zsh vs Bash – Which one you should be using?
Z-shell (or Zsh) is an interactive Bourne-like shell and a powerful command-line tool for scripting language including shell scripting. It’s known for its abundance of interactive and customizable features. Zsh […]

Repository changed its ‘Origin’ value from ‘Google, Inc.’ to ‘Google LLC’ – How to fix?
If you’re on Debian or Ubuntu and using Google official repositories for updating your system, you might have received the following error. This is such an obvious error. Google Inc […]

How to kill a zombie process in Linux?
On Unix and Unix-like computer operating systems, a zombie process or defunct process is a process that has completed execution (via the exit system call) but still has an entry in the process table: it is […]