It is almost impossible not having heard about or not having used LVM: it is one of the pillars of every Linux distribution from decades ago. Almost everyone using Linux has used it to create or modify the basic storage structures of its Linux system. The trouble is that very often people are focused on the specific task they are onto, and neglect the time to investigate its amazing features. The goal of LVM Tutorial - A thorough howto on the Logical Volume Manager is to provide an easy yet comprehensive explanation on the most interesting features of LVM that it is very likely you will need to use sooner or later.

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Git is certainly the most popular Source Code Management (SCM) software: it is broadly used in almost every recent open source project, and even a lot of emblazoned legacy projects switched to it over the years.

In the previous post we thoroughly learned how to use it to version control sources, working only on personal - so local - repositories.

GIT Tutorial - A thorough Git Howto About Using Remotes completes our trip on learning how to professionally use Git, showing you how to link the personal local repository to shared remote bare repositories.
Knowing how to deal with this topic is of course a mandatory skill, since this is the only way you have to cooperate and work with other developers.

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DevOps (and of course DevSecOps) are getting more and more adopted by companies: these methodologies rely on several frameworks and software skills, and working with a modern Source Code Management (SCM) such any kind of software implementing Git is certainly a must for every DevOps professional. This post is the first of a set of posts dedicated to Git and is aimed at providing a GIT Tutorial - A thorough Version Control with Git Howto on personal repositories, giving guidelines to proficient operating with it.
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GnuPG is a freely available command line encryption suite based on OpenPGP encryption library, and it is probably the most used encryption suite in the world. Every IT professional sooner or later face use cases that require to know how to handle it, but the point is that, despite a trivial usage of this suite may look quite easy, there are some not so obvious nuances that if known can really improve the experience, also saving from making some hidden mistakes that can really painful if anything would go wrong.

This is a quick, easy yet comprehensive GPG tutorial with the aim to provide a quick yet thorough explanation of how to safely use this amazing encryption suite.

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AWK is a powerful pattern scanning and processing language developed by Alfred Aho, Peter Weinberger and Brian Kernighan at Bell Labs - the name of this tool is indeed derived by concatenating the letter of their surnames to one another. It is one of that tools that every Linux professionals (not only the more seasoned ones) must be skilled on, since it is broadly used in a lot of shell scripts that very often are inherited from predecessors and that must be maintained: the sad truth is that very often is not worth the effort to rewrite them using other more modern languages, so knowing how to deal with it can really ease your life. And anyway, ... sometimes it requires much less time to code an AWK one liner than a Python script, so knowing how and when to use AWK is certainly a valuable skill still nowadays.
The aim of "The Ultimate AWK Tutorial For Professionals" is not to provide a complete explain about how to code with AWK - there are more modern and handy languages such as Python nowadays: I just want to provide a very quick yet comprehensive walkthrough on it focusing on how to write AWK one-liners that are often embedded in shell scripts or that you can use to sort out common system administration tasks. That's why I'm also showing some real-life use cases with AWK one-liners that can very quickly and easily sort things out.

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Managing Red Hat Network Satellite clients with Ansible roles and playbooks is a very powerful feature of Red Hat Network Satellite Server 6, as well as of its upstream project Katello. Conversely from Puppet, that requires the client host to install its agent package and to be registered to the Puppet master running on the Satellite or Capsule, Ansible does not require installing anything, since it relies on SSH or, to tell it in Red Hat Network Satellite 6 terms, it relies on remote execution with SSH.

This post shows you how to manage client hosts using Ansible, either executing the Ansible roles assigned to the host group the client host belongs to, or running Ansible playbooks using Job Templates.

The Linux distribution used in the examples is CentOS 7, but you can of course easily adapt it to any other Red Hat and derived Linux distribution.

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