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Ansible is an open source configuration management, application deployment as well software provisioning tool that is used to deploy, configure & manage servers. Due to ease in using Ansible is one of the easiest & most popular automation tools.

It uses YAML, which is easy to learn & does not require you to learn a complicated programming language like Ruby (used in puppet & chef).

Also, it does not require any special agent to be installed on client machines & only requires client machines to have python and ssh installed, both of these are usually available on systems.

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VPN is now becoming a must-have for using the internet. Whether you want to secure your internet traffic or want to access some content on a streaming service that is currently not available in your country.

Whatever the reason, VPN is now becoming a necessity, especially since there are privacy concerns looming around & also people do want to know which is the best VPN for PC or best VPN for Torrenting or Streaming Netflix, as there might be some restrictions in the country where you belong to.

But first for the uninitiated, a brief on VPN.

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Like any other application or server, Redis installations might also be susceptible to unauthorized access or intrusions, if we have not secured it properly. In this tutorial, we will focus on securing Redis server to avoid any unauthorized access or intrusions.

Redis is an open source, in-memory data structure store or a key-value store that can be used as a cache for application, as a database server or even as a message broker.

In our previous tutorials, we have already discussed the installation & also setting up a master-slave like architecture for the Redis server.

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Having a comprehensive data protection policy in place is now a fundamental practice to help ensure your data manages to weather all the storms that can be thrown at it. Saying that it should be done is the easy part, actually doing it gets more complex, and laborious, depending on the policy in place and what standards and laws the organization needs to adhere to.

Fortunately, for Linux users there a tool exists that makes backing up data a breeze, and it can all be done from the command line.

Utilizing rsync’s most basic features allows the user to backup, modify, and delete files via the use of a remote server.

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Glances is an open source real time Linux server monitoring system that aims at providing as much as information possible in as minimum as space possible. Glances is like top command but more refined with many more features & much more real time information of your Linux system.

Glances provide information regarding memory, CPU, Disk IO , file system, Uptime, processes, interfaces, alerts & many other system information.

One of the best features of Glances is that it can work in server/client mode. We can perform remote monitoring of the systems using a Web interface or through terminal/CLI & we can also export stats to a file.

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Earlier we have discussed how we can configure network connections using three different methods i.e. by editing network interface file, by using GUI & by using nmtui command. In this tutorial, we are going to use two other methods to configure network connections on our RHEL/CentOS machines. We are going to discuss 'nmcli' command & 'ifconfig' command in Linux.First utility that we will be using is ‘nmcli’ command & we can configure network on almost any Linux distribution using this method.

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SS command in Linux is used to get various network/socket connection-related information from a Linux system. Previously we had used the Netstat command to perform the same operations but it has been long deprecated & was replaced with the ss command in Linux.

SS command is much faster than netstat & capable of showing much more information than netstat. Those familiar with the Netstat command need not worry as the options used with the ss command are similar to netstat.

In this tutorial, we will learn the usage of the SS command with the help of SS command examples.

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We have seen a tremendous increase in demand for automation in the IT industry & IaaC, Infrastructure as a Code is a must-needed skill to possess. There are a number of tools available for Automation/IaaC & Terraform is one such tool.

Terraform is a great tool for automating our infrastructure by converting all our infrastructure as code. We can deploy resources using only the terraform scripts.

The great thing about terraform is that it supports almost all cloud providers like AWS, GCP, Azure, IBM Cloud, etc & also supports in-house solutions.

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Dockerfile is a text file that contains a list of commands that are used to build a docker image automatically. Basically, a docker file acts as a set of instructions that are needed to build a docker image.

We have earlier discussed how to create a docker container & also learned some important commands for managing the containers.

In this tutorial, we will learn about how to create a dockerfile, all its parameters/commands with the dockerfile example.

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We will use one of the previously created Dockerfiles to create a Docker image & will then upload the created image to Docker Hub.

To simply explain Docker Hub, it's a public registry that has over 15000 images that can be directly used or can be used to create a custom Docker image. Docker Hub is directly maintained by Docker.

So let's start with our tutorial on how to create Docker Image, but before we do that let's discuss some pre-requisites.

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Yum command in Linux is the default package manager for RPM packages on RHEL & CentOS. And most of you working on these OS should be familiar with it.

In this article, we are going to discuss some Yum tips & tricks that we normally don't know or use but are pretty useful.

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Learn how to perform some of the common operations for Gitlab Setup, once you have installed the Gitlab server on your systems. We must be aware of how to perform following common operations as mentioned below,

Add SSH keys Create/Remove User Create/Remove Groups Create Project

In this Gitlab tutorial, we are going to discuss just that.

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Learn to create functions for our Bash / shell scripts. Learning how to create a function is an important skill required for BASH scripting.

When we are writing our scripts, we might see ourselves using a section of the script over and over again like using a loop that is checking a condition many times in a script. So rather than writing a section of the script over & over again, we will create that section of script as a Functions aka Bash Functions also.

Functions are like a mini-script inside the scripts. We will create a function with a name & whenever that function is required, we will just type the name of the function rather than typing the whole section of a script again & again.

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Learn some simple ansible commands that we will use to manage our infrastructure. Consider this as an Ansible commands cheatsheet.

So let us start by looking at the syntax of a simple ansible commands,

$ ansible <group> -m <module> -a <arguments>

Here, we can also use a single host or all in place of <group> & <arguments> are optional to provide.

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This simple tutorial details the process to install Python PIP on Ubunu & also on CentOS / RHEL.

PIP is a package manager for python-based software, PIP actually is a recursive acronym for 'PIP installs python' or 'PIP install packages'.

Using PIP, we can install, uninstall the python based packages along with their required dependencies. Many of the packages can also be found at PyPI (Python Package Index).

[linuxtechlab]

Learn How to install Python3 (3.9) & PIP on Ubuntu (and other Linux versions)

PIP is a package manager for python-based software, PIP actually is a recursive acronym for 'PIP installs python' or 'PIP install packages'.

Using PIP, we can install, uninstall the python based packages along with their required dependencies. Many of the packages can also be found at PyPI (Python Package Index).

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Using Linux means using command line interface aka CLI aka terminal on regular basis. Being good at using CLI is what separates a casual Linux user & an expert.

In this tutorial, we will learn about some useful Linux keyboard shortcuts that can increase your efficiency as well as your productivity.