ubuntu-grub-menu

How to boot Ubuntu 18.04 into emergency and rescue mode

Objective

Learning about systemd emergency and rescue targets and how to boot the system into them

Requirements

  • No special requirements

Difficulty

EASY

Conventions

  • # – requires given linux commands to be executed with root privileges either
    directly as a root user or by use of sudo command
  • $ – requires given linux commands to be executed as a regular non-privileged user

Introduction

Systemd has nowadays become the de facto standard init system for all the major Linux distributions.

Superseding SysV and upstart, it also replaced the classical way of defining system runlevels, using system targets, a special type of unit.

In this tutorial we will see how to boot an Ubuntu 18.04 system into the emergency and rescue systemd targets, and what kind of environment they provide to the users.

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How to install Varnish cache server with Nginx on Ubuntu 18.04 Bionic Beaver Linux

Objective

The objective is to install and configure a Varnish Cache server with Nginx on Ubuntu 18.04 Bionic Beaver Linux. Varnish is a fast caching server which sits in front of any web server and serves previously cached pages, hence, improving the website’s response time.

Operating System and Software Versions

  • Operating System: – Ubuntu 18.04 Bionic Beaver Linux
  • Software: – Varnish 5.2 or higher

Requirements

Privileged access to your Ubuntu System as root or via sudo command is required.

Difficulty

MEDIUM

Conventions

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How to install Litecoin wallet on Ubuntu 18.04 Bionic Beaver Linux

Objective

The objective is to install Electron LTC, the Litecoin wallet on Ubuntu 18.04 Bionic Beaver Linux desktop

Operating System and Software Versions

  • Operating System: – Ubuntu 18.04 Bionic Beaver
  • Software: – Electrum-LTC 3.0.6.2 or higher

Requirements

Privileged access to your Ubuntu System as root or via sudo command is required.

Difficulty

EASY

Conventions

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How to install Bitcoin Wallet on Ubuntu 18.04 Bionic Beaver Linux

Objective

The objective is to download, verify and install Electrum Bitcoin wallet on Ubuntu 18.04 Bionic Beaver Linux Desktop

Operating System and Software Versions

  • Operating System: – Ubuntu 18.04 Bionic Beaver
  • Software: – Electrum 3.0.6 or higher

Requirements

Privileged access to your Ubuntu System as root or via sudo command is required.

Difficulty

EASY

Conventions

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Image showing a Puppet sync error message

How to use Puppet environments in Linux to safely update an agent

Objective

Create and use puppet environments to test new configuration before updating a live production system.

Operating System and Software Versions

  • Operating System: Any major linux distribution e.g. Ubuntu, Debian, CentOS
  • Software: puppet and puppet-master

Requirements

Privileged access to the puppet master server and the puppet client node.

Conventions

  • # – requires given linux commands to be executed with root privileges either directly as a root user or by use of sudo command
  • $ – given linux commands to be executed as a regular non-privileged user

Introduction

Most Puppet installations begin life as a master server running a single branch. The master contains all the manifests and other configuration for all the Puppet agents that are synced to it. This is a fine place to begin but there will rapidly arrive a time when an update needs pushing that has the potential to break a production server. Hoping for the best is not the best way to proceed.

Puppet provides the tools to separate entire branches of configuration. These are called environments. A Puppet environment is a way to supply an isolated group of agent nodes with their own dedicated configuration. Each environment contains an entire Puppet configuration tree and can be considered as a separate Puppet master server.

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Add MongoDB Source On Ubuntu 18.04

Install The MEAN Stack On Ubuntu 18.04 Bionic Beaver Linux

Objective

Install the MEAN stack on Ubuntu 18.04

Distributions

Ubuntu 18.04

Requirements

A working install of Ubuntu 18.04 with root privileges

Difficulty

Easy

Conventions

  • # – requires given linux commands to be executed with root privileges either directly as a root user or by use of sudo command
  • $ – requires given linux commands to be executed as a regular non-privileged user

Introduction

The MEAN stack is quickly becoming a favorite among web developers. MEAN stands for MongoDB, ExpressJS, AngularJS, and NodeJS. Clearly, this is a JavaScript heavy tech stack, so it’s not for people who don’t like JS. However, it does provide an excellent framework for building lightweight and fully capable web applications.

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How to set up Ruby on Rails on Ubuntu 18.04 Bionic Beaver Linux

Objective

The objective is to install Ruby on Rails on Ubuntu 18.04 Bionic Beaver Linux. First we will perform a standard installation from Ubuntu 18.04 repositories. The second part of this tutorial will show you how to use Ruby Version Manager (RVM) to install the latest Ruby.

Operating System and Software Versions

  • Operating System: – Ubuntu 18.04 Bionic Beaver Linux

Requirements

Privileged access to your Ubuntu 18.04 Bionic Beaver is required to install Ruby on Rails on Ubuntu 18.04 and/or prerequisites.

Difficulty

EASY

Conventions

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bash scripting

How to modify scripts behavior on signals using bash traps

Objective

The objective of this tutorial is to describe how to use the bash shell trap builtin to make our scripts able to perform certain actions when they receive a signal or in other specific situations.

Requirements

  • No special requirements

Difficulty

EASY

Conventions

  • # – requires given linux commands to be executed with root privileges either
    directly as a root user or by use of sudo command
  • $ – requires given linux commands to be executed as a regular non-privileged user

Introduction

bash scriptingWhen writing scripts that are meant to run for a considerable time, it’s very important to increase their robustness by making them able to react to system signals, executing specific actions when some of them are received. We can accomplish this task by using the bash trap builtin.

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