In 2020, we will be seeing the boom in the Internet of Things (IoT) space continue to grow with more explosions in the number and variety of IoT solutions in the market. Additionally, large amounts of funding are being deployed at IoT startups. It also happens to be that industry…

How to install OpenVPN using Docker

In today’s day and age, with restrictions being imposed, there is an immense need to use VPN servers. There are many VPN providers available out there for free and paid use but these also require a degree of trust and might also sometimes seem to be unreliable.

Well, there is…

Why Have an SSH Tarpit?

If you have any servers that you access using SSH (Secure Socket Shell) connection, you’ll be familiar with how it can be used my hackers to gain access to your servers. However, you’ll also notice through reviewing your server authentication logs look like something like below:

Docker Certified Associate (DCA)

Continuing where we had previously left off. Here is “Set-2" in our series of DCA Practice Questions. Remember, the more you practice, the better are your chances. 😉

  1. What is a grant made up of in Docker’s Role-Based Access Controls (RBAC)? (select three)

Options are :

  • Certificate
  • Role
  • Resource Collection

Docker Certified Associate (DCA)

Docker is quite the buzz tool nowadays, it is a tool that is making it easier to create, deploy, and run applications by using containers.

In today’s job market having Docker skills proves to be of immense importance and the Docker Certified Associate (DCA) exam is designed to validate that…

JavaScript Promises: Promise.all vs Promise.allSettled vs Promise.race vs Promise.any

On your way to become a “JavaScript Superstar” and “Promises whizz”, you’ll need to master the concept of handling multiple promises at the same time. …

Easy PGP Encryption using Node.js

What Is Pretty Good Privacy Encryption?

Pretty Good Privacy (PGP) encryption is an encryption system used for sending and receiving encrypted emails and sensitive files. Over the years, PGP has become the de facto standard for email security.

Essentially, PGP uses a combination of two forms of encryption: symmetric key encryption and public-key encryption. …


OpenStreetMaps (OSM) is quoted to be a “free wiki world map”. The OSM tile server is essentially a web server specialized in delivering raster maps. It serves them as static ties and is also able to perform rendering in real-time or providing cached images.

Install Dependencies

we will start by updating our…

What Is Tee?

tee on Linux is a command-line tool, it reads from the standard input and is the capability of writing results to the terminal's standard output and files at the same time. This essentially lets you store and view (both at the same time) the output at any time.

How to Use It?

Let’s illustrate…

Why Screen?

screen is this awesome software tool in Linux that provides you the ability to spring-up and use multiple shell sessions from a single ssh session. Screen essentially acts as a terminal multiplexer emulator that is packed with features (just look at the size of its man page, you'll know 😝)

Zubair Ahmed

Chief Technology Officer at RAZRLAB

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