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This example will show you how to create users in Linux, looking at the two different available commands: the default utility, useradd; and a script that acts as more friendly front-end for the default utility, which is named adduser. For this example, Linux Mint 17.03 has been used. 1. How users are organized The existing users of the system are ...

This article is part of our Academy Course titled PostgreSQL Database Tutorial. In this course, we provide a compilation of PostgreSQL tutorials that will help you set up and run your own database management system. We cover a wide range of topics, from installation and configuration, to custom commands and datatypes. With our straightforward tutorials, you will be able to ...

In this tutorial we will see how to add users to groups in Linux, looking at the different possibilities (existing or non-existing users), and taking into account also the different types of groups users can belong to (primary and secondary groups). For this example, Linux Mint 17.03 has been used. 1. How groups are organized Linux defines the groups in ...

When it comes to documenting the APIs (especially the REST ones), having the cURL samples that one can try out and play around with has become the defacto standard these days. However if you actually want to read through the response body, look up certain piece of information or just simply check the integrity of the response itself, you will ...

cURL is an incredibly flexible and powerful tool data transferring tool, that supports a wide variety of protocols, being the HTTP (and HTTPS) the most used. cURL library is available for many programming languages, but in this example we will see how to use it from the command line. For this tutorial, Mint 17.3 has been used. 1. Installation cURL ...

One of the most critical jobs a system administrator has to continuously be dealing with is the permission administration. The most small carelessness with the permissions can lead to a security hole in the system. This example will show how are changed the permissions, a task for which chmod command is used For this example, Linux Mint 17.3 has been ...

For the latter part of the week I’ve been running some tests against Neo4j which generate a bunch of log files and I wanted to filter those files based on the time they were created to do some further analysis. This is an example of what the directory listing looks like: $ ls -alh foo/database-agent-* -rw-r--r-- 1 markneedham wheel 2.5K ...

I recently wanted to parse some text out of a bunch of files so that I could do some sentiment analysis on it. Luckily the text I want is at the end of the file and doesn’t have anything after it but there is text before it that I want to get rid. The files look like this: # text ...

Spawning services across multiple Docker engines is a very cool thing, but those services need to connect each other and be found by public-facing nodes in order to be routed to users. A way to achieve that is to use NGINX as a reverse proxy by defining one or more public-facing nodes. These nodes are going to have NGINX configured ...