PFX certificate: extract the certificate and the private key

In this tutorial, I will explain how to extract the certificate and the private key from a certificate in PFX format with OpenSSL. The easiest way to use OpenSSL is to use a Linux computer. 1. Copy the PFX file to your computer where OpenSSL is installed. 2. The first step will be to extract …

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Docker: installation and concrete use on Ubuntu

Introduction In this tutorial, I will explain to you how to install Docker on Ubuntu and then through a concrete example how and why to use Docker. At the time of writing this tutorial (in 2021) as SysAdmin, I was having a hard time finding a concrete use for containers including Docker (so I’ll let …

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SSH: authentication by keys

In this tutorial, I will explain how to connect to a linux server / computer in SSH without password using a key pair (private / public). Generate the key pair with ssh-keygen To generate a pair of keys, you must have an SSH client available, it is possible to do it from Windows 10 or …

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Ubuntu: create a user and add it to the sudo group

Small memo to create a user on Ubuntu and add it to the sudo group: Enter the password for the current user (sudo) if necessary, then enter the password for the new account twice and enter additional information as required. Confirm the information by pressing Enter. Now we add the user to the sudo group. …

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Ubuntu : install the FusionInventory agent

In this tutorial, I will explain how to install the FusionInventory agent on Ubuntu in order to bring it up in your GLPI inventory. Installation is done from the command line. Installation of prerequisites To function correctly, it is necessary to install several packages first. Enter the command line below to install all dependencies : …

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Guacamole: manage access to your IT environment

In this tutorial, I will explain how to install Guacamole on Ubuntu, configure access to equipment and use it. Before starting the technique, I will first introduce you to Apache Guacamole and especially why to put it in place. What is Guacamole? No, I’m not going to talk about the avocado sauce recipe in this …

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Ubuntu: install and configure the SNMP service

In this tutorial, I will explain to you how to install and configure the SNMP service on Ubuntu, which will then allow you to monitor the server using PRTG or Centreon for example. We will first install the service on the Ubuntu server and then configure it so that it is accessible by the network …

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Linux: display logs in real time

In this “how” tutorial, I will explain how to display logs in real time saved in a file in SSH This type of manipulation is useful when you want to see what is happening in real time. To illustrate this tutorial, I used the access logs of an NGINX server. Use the tail -f command …

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