https://rdr-it.com/en/category/linux/System administration, virtualization, security and tools for IT professionals.en-USFri, 09 Oct 2026 17:31:24 +0000https://rdr-it.com/en/generate-a-pfx-certificate-from-a-key-and-a-crt-file/Wed, 09 Sep 2026 04:30:00 +0000https://rdr-it.com/en/generate-a-pfx-certificate-from-a-key-and-a-crt-file/In this tutorial, I’ll explain how to convert a certificate to PFX format from .key and .crt files. To convert a certificate to PFX format, you’ll need OpenSSL. In this …https://rdr-it.com/en/ubuntu-display-s-m-a-r-t-data-for-an-nvme-drive/Wed, 29 Jul 2026 04:30:00 +0000https://rdr-it.com/en/ubuntu-display-s-m-a-r-t-data-for-an-nvme-drive/In this tutorial, I’ll explain how to view the S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) data for an NVMe drive on Ubuntu using the command line. …https://rdr-it.com/en/ubuntu-testing-disk-performance-from-the-command-line/Fri, 24 Jul 2026 04:30:00 +0000https://rdr-it.com/en/ubuntu-testing-disk-performance-from-the-command-line/In this tutorial, I’ll explain how to test the read and write performance of a disk on Ubuntu using the command line. To give you some points of comparison, I ran the …https://rdr-it.com/en/rsync-how-to-copy-back-up-files-on-linux/Wed, 08 Jul 2026 04:30:00 +0000https://rdr-it.com/en/rsync-how-to-copy-back-up-files-on-linux/Introduction to rsync LinuxIn this tutorial, I’ll explain how to usersync rsync (Remote Synchronization) to make copies or backups. rsynIt is a folder synchronization …https://rdr-it.com/en/ubuntu-how-to-block-updating-a-specific-package-with-apt-mark/Mon, 23 Feb 2026 06:00:00 +0000https://rdr-it.com/en/ubuntu-how-to-block-updating-a-specific-package-with-apt-mark/Find out how to block the update of a package under Ubuntu with apt-mark hold. Simple tutorial to freeze a version and avoid unwanted updates.https://rdr-it.com/en/ssh-resolve-error-warning-unprotected-private-key-file/Wed, 21 May 2025 04:30:00 +0000https://rdr-it.com/en/ssh-resolve-error-warning-unprotected-private-key-file/In this tutorial, I will explain how to resolve the following error : Warning: unprotected private key file! when you try to SSH from Linux to another SSH server with a …https://rdr-it.com/en/ubuntu-24-04-install-nginx-1-27-x/Wed, 26 Mar 2025 05:30:00 +0000https://rdr-it.com/en/ubuntu-24-04-install-nginx-1-27-x/In this tutorial, I will explain how to install Nginx version 1.27.X on Ubuntu 24.04 (this also works for Ubuntu version 22.04). At the time of writing this tutorial, the …https://rdr-it.com/en/configure-a-reverse-proxy-with-apache-on-ubuntu/Wed, 04 Dec 2024 05:30:00 +0000https://rdr-it.com/en/configure-a-reverse-proxy-with-apache-on-ubuntu/Introducing the Reverse Proxy In this tutorial, I will explain how to configure a reverse proxy with Apache on Ubuntu (By adapting the Apache installation commands, this …https://rdr-it.com/en/ubuntu-busybox-solve-unexpected-inconsistyency-error/Wed, 31 Jul 2024 04:30:00 +0000https://rdr-it.com/en/ubuntu-busybox-solve-unexpected-inconsistyency-error/In this tutorial, I will tell you how to resolve the UNEXPECTED INCONSISYENCY error when starting the computer in BusyBox mode. During a sudden shutdown with a disk …https://rdr-it.com/en/download-glpi-from-command-line-on-linux/Wed, 17 Jul 2024 04:30:00 +0000https://rdr-it.com/en/download-glpi-from-command-line-on-linux/In this tutorial, I will explain how to download GLPI from the command line with wget, unzip it and move it to the virtualhost folder. If you have a Web server under …https://rdr-it.com/en/ubuntu-22-04-install-a-lamp-server-linux-apache-mariadb-php/Wed, 03 Jul 2024 04:30:00 +0000https://rdr-it.com/en/ubuntu-22-04-install-a-lamp-server-linux-apache-mariadb-php/LAMP Overview In this tutorial, I will explain how to install a LAMP server on Ubuntu 22.04. LAMP stands for Linux Apache MariaDB PHP, it is a set of software that we …https://rdr-it.com/en/ubuntu-add-an-lvm-disk-and-volume/Wed, 24 Apr 2024 04:30:00 +0000https://rdr-it.com/en/ubuntu-add-an-lvm-disk-and-volume/In this tutorial, I will explain how to add an additional disk to an Ubuntu machine and create a new LMV volume for this disk. To explain this tutorial, I will start from …https://rdr-it.com/en/postfix-configure-a-mail-relay-mta-on-ubuntu/Wed, 20 Mar 2024 05:30:00 +0000https://rdr-it.com/en/postfix-configure-a-mail-relay-mta-on-ubuntu/In this tutorial, I will explain to you how to install (it’s the easiest) and configure Postfix on Ubuntu as an email relay to send emails from applications, equipment …https://rdr-it.com/en/how-to-display-the-list-of-users-on-linux-from-the-command-line/Wed, 14 Feb 2024 05:30:00 +0000https://rdr-it.com/en/how-to-display-the-list-of-users-on-linux-from-the-command-line/ How to display the list of users on Linux from the command line? Use the command: sudo cat /etc/passwd | cut -d: -f1 to list users in the file /etc/passwd The easiest …https://rdr-it.com/en/ubuntu-22-04-install-docker/Wed, 07 Feb 2024 05:30:00 +0000https://rdr-it.com/en/ubuntu-22-04-install-docker/In this tutorial, I will show you a script to install Docker and Docker Compose on Ubuntu 22.04. Today more and more applications are available in containers with Docker, …https://rdr-it.com/en/duf-show-available-disk-space-on-ubuntu/Wed, 29 Nov 2023 09:20:07 +0000https://rdr-it.com/en/duf-show-available-disk-space-on-ubuntu/In this tutorial, I will explain how to install duf to show available disk space on Ubuntu. DUF is a command line utility that allows you to view available disk space on …https://rdr-it.com/en/ufw-delete-a-rule/Wed, 22 Nov 2023 09:15:24 +0000https://rdr-it.com/en/ufw-delete-a-rule/In this tutorial, I will explain how to easily delete a firewall rule managed by UFW. UFW is a command line interface that simplifies the use of iptables rules.https://rdr-it.com/en/ubuntu-server-configure-the-time-zone/Wed, 27 Sep 2023 13:37:54 +0000https://rdr-it.com/en/ubuntu-server-configure-the-time-zone/In this tutorial, I will explain how to configure the time zone called timezone on Ubuntu Server. Unlike the Desktop version, when installing the server version of …https://rdr-it.com/en/ubuntu-add-a-certificate-from-an-internal-certificate-authority-40287/Wed, 13 Sep 2023 04:30:00 +0000https://rdr-it.com/en/ubuntu-add-a-certificate-from-an-internal-certificate-authority-40287/In this tutorial, I will show you how to add the certificate of an internal CA on an Ubuntu machine. In business, we often use an Enterprise Certification Authority, …https://rdr-it.com/en/ubuntu-enable-the-firewall-and-manage-it-with-ufw/Wed, 24 May 2023 04:30:00 +0000https://rdr-it.com/en/ubuntu-enable-the-firewall-and-manage-it-with-ufw/In this tutorial, I will explain how to activate the firewall on a computer with Ubuntu and manage it with UFW. UFW for Uncomplicated Firewall is a simplified Netfilter …