Ubuntu Server Cookbook

By Uday R. Sawant

About This Book

• Master the skills to setup secure and scalable web services with popular tools like Apache, Nginx, MySQL and HAProxy
• Set up your own cloud with Open Stack and quickly deploy applications with Docker or LXD
• Packed with clear, step-by-step recipes to let you protect you valuable data with your own chat servers, code hosting and collaboration tools.

Who This Book Is For

Ubuntu Server Cookbook is intended for system administrators with a basic understanding of Linux operating system. If you are a software developer or a newbie system administrator and want to setup your own servers, this book is an ideal guide for you. You are not required to have an in-depth knowledge or hands-on experience with Ubuntu, but you should know the basic commands for directory navigation, file management, and file editing tool. An understanding of computer networks and Internet is advisable.

• Language: English
• Publisher: Packt Publishing
• Release date: Jun 30, 2016
• ISBN: 9781785887987

Book preview

Table of Contents

Ubuntu Server Cookbook

Credits

About the Author

www.PacktPub.com

eBooks, discount offers, and more

Why Subscribe?

Preface

What this book covers

What you need for this book

Who this book is for

Sections

Getting ready

How to do it…

How it works…

There's more…

See also

Conventions

Reader feedback

Customer support

Downloading the example code

Downloading the color images of this book

Errata

Piracy

Questions

1. Managing Users and Groups

Introduction

Creating a user account

Getting ready

How to do it…

How it works…

There's more…

See also

Creating user accounts in batch mode

Getting ready

How to do it...

How it works…

Creating a group

Getting ready

How to do it...

How it works…

There's more…

See also

Adding group members

Getting ready

How to do it…

How it works…

There's more…

Deleting a user account

Getting ready

How to do it...

How it works…

There's more…

See also

Managing file permissions

Getting ready

How to do it…

How it works…

There's more…

Getting root privileges with sudo

Getting ready

How to do it...

How it works…

There's more…

Setting password less sudo

Other uses of sudo

See also

Setting resource limits with limits.conf

Getting ready

How to do it...

How it works…

There's more…

Setting up public key authentication

Getting ready

How to do it...

How it works…

Working of SSH authentication

There's more…

Troubleshooting SSH connections

SSH tools for the Windows platform

See also

Securing user accounts

How to do it...

How it works…

2. Networking

Introduction

Connecting to a network with a static IP

Getting ready

How to do it…

How it works…

There's more…

IPv6 configuration

See also

Installing the DHCP server

Getting ready

How to do it…

How it works…

There's more…

Installing the DNS server

Getting ready

How to do it…

How it works…

See also

Hiding behind the proxy with squid

Getting ready

How to do it…

How it works…

There's more…

Access control list

Set cache refresh rules

Sarg – tool to analyze squid logs

Squid guard

See also

Being on time with NTP

How to do it…

How it works…

There's more…

See also

Discussing load balancing with HAProxy

Getting ready

How to do it…

How it works…

There's more …

See also

Tuning the TCP stack

Getting ready…

How to do it…

How it works…

See also

Troubleshooting network connectivity

Getting ready

How to do it…

There's more…

Securing remote access with OpenVPN

Getting ready…

How to do it…

How it works…

There's more…

Securing a network with uncomplicated firewall

Getting ready

How to do it…

There's more…

See also

Securing against brute force attacks

Getting ready

How to do it…

How it works…

There's more…

Discussing Ubuntu security best practices

Getting ready

How to do it…

How it works…

See also

3. Working with Web Servers

Introduction

Installing and configuring the Apache web server

Getting ready

How to do it…

How it works…

There's more…

HTTP version 2 support

See also

Serving dynamic contents with PHP

Getting ready

How to do it…

How it works…

PHP settings

There's more…

Installing the LAMP stack

Upgrading PHP under Ubuntu 14

Hosting multiple websites with a virtual domain

Getting ready

How to do it…

How it works…

See also

Securing web traffic with HTTPS

Getting ready

How to do it…

How it works…

There's more…

See also

Installing Nginx with PHP_FPM

Getting ready

How to do it…

How it works…

There's more…

See also

Setting Nginx as a reverse proxy

Getting ready

How to do it…

How it works…

There's more…

HAProxy and Varnish

See also

Load balancing with Nginx

Getting ready

How to do it…

How it works…

There's more…

See also

Setting HTTPs on Nginx

Getting ready

How to do it…

How it works…

See also

Benchmarking and performance tuning of Apache

Getting ready

How to do it…

There's more…

See also

Securing the web server

Getting ready

How to do it…

How it works…

See also

Troubleshooting the web server

Getting ready

How to do it…

Web server not accessible

Virtual host not accessible

Access denied or forbidden errors

Apache downloads .php files

4. Working with Mail Servers

Introduction

Sending e-mails with Postfix

Getting ready

How to do it…

How it works…

See also

Enabling IMAP and POP3 with Dovecot

Getting ready

How to do it…

How it works…

See also

Adding e-mail accounts

Getting ready

How to do it…

How it works…

There's more…

Web console for virtual mailbox administration

See also

Mail filtering with spam-assassin

Getting ready

How to do it…

How it works…

There's more…

See also

Troubleshooting the mail server

Getting ready

How to do it…

See also

Installing the Zimbra mail server

Getting ready

How to do it…

How it works…

There's more…

See also

5. Handling Databases

Introduction

Installing relational databases with MySQL

Getting ready

How to do it…

How it works…

There’s more…

Securing MySQL installation

See also

Storing and retrieving data with MySQL

Getting ready

How to do it…

How it works…

Importing and exporting bulk data

How to do it…

See also

Adding users and assigning access rights

Getting ready

How to do it…

How it works…

There’s more…

Removing user accounts

Setting resource limits

See also

Installing web access for MySQL

Getting ready

How to do it…

How it works…

There’s more…

See also

Setting backups

Getting ready

How to do it…

How it works…

See also

Optimizing MySQL performance – queries

Getting ready

How to do it…

How it works…

There’s more…

Sharding MySQL

See also

Optimizing MySQL performance – configuration

Getting ready

How to do it…

How it works…

There’s more…

Percona configuration wizard

MySQL table compression

See also

Creating MySQL replicas for scaling and high availability

Getting ready

How to do it…

How it works…

There’s more…

See also

Troubleshooting MySQL

Getting ready

How to do it…

See also

Installing MongoDB

Getting ready

How to do it…

How it works…

See also

Storing and retrieving data with MongoDB

Getting ready

How to do it…

How it works…

There’s more…

See also

6. Network Storage

Introduction

Installing the Samba server

Getting ready

How to do it…

How it works…

There's more…

Tools for personal file sharing

See also

Adding users to the Samba server

Getting ready

How to do it…

How it works…

There's more…

See also

Installing the secure FTP server

Getting ready

How to do it…

How it works…

There's more…

See also

Synchronizing files with Rsync

How to do it…

How it works…

There's more…

See also

Performance tuning the Samba server

Getting ready

How to do it…

How it works…

Troubleshooting the Samba server

How to do it…

Checking network connectivity

Checking the Samba service

Checking Samba logs

Checking Samba configuration

See also

Installing the Network File System

Getting ready

How to do it…

How it works…

There's more…

See also

7. Cloud Computing

Introduction

Creating virtual machine with KVM

Getting ready

How to do it…

How it works…

There's more…

See also

Managing virtual machines with virsh

Getting ready

How to do it…

How it works…

There's more…

Easy cloud images with uvtool

See also

Setting up your own cloud with OpenStack

Getting ready

How to do it…

How it works…

There's more…

See also

Adding a cloud image to OpenStack

Getting ready

How to do it…

How it works…

There's more…

See also

Launching a virtual instance with OpenStack

Getting ready

How to do it…

How it works…

There's more…

See also

Installing Juju a service orchestration framework

Getting ready

How to do it…

How it works…

There's more…

See also

Managing services with Juju

Getting ready

How to do it…

How it works…

There's more…

See also

8. Working with Containers

Introduction

Installing LXD, the Linux container daemon

Getting ready

How to do it…

How it works…

There's more…

See also

Deploying your first container with LXD

Getting ready

How to do it…

How it works…

There's more…

See also

Managing LXD containers

Getting ready…

How to do it…

There's more…

See also

Managing LXD containers – advanced options

How to do it…

How it works…

Setting resource limits on LXD containers

How to do it…

How it works…

There's more…

See also

Networking with LXD

Getting ready

How to do it…

How it works…

There's more…

See also

Installing Docker

Getting ready

How to do it…

How it works…

There's more…

See also

Starting and managing Docker containers

Getting ready

How to do it…

How it works…

There's more…

See also

Creating images with a Dockerfile

Getting ready

How to do it…

How it works…

There's more…

See also

Understanding Docker volumes

Getting ready

How to do it…

How it works…

See also

Deploying WordPress using a Docker network

How to do it…

How it works…

There's more…

See also

Monitoring Docker containers

How to do it…

How it works…

There's more…

See also

Securing Docker containers

How to do it…

See also

9. Streaming with Ampache

Introduction

Installing the Ampache server

Getting ready

How to do it…

How it works…

There's more…

See also

Uploading contents and creating catalogs

Getting ready

How to do it…

How it works…

Setting on-the-fly transcoding

Getting ready

How to do it…

Enabling API access for remote streaming

Getting ready

How to do it…

How it works…

Streaming music with Ampache

Getting ready

How to do it…

10. Communication Server with XMPP

Introduction

Installing Ejabberd

Getting ready

How to do it…

How it works…

See also

Creating users and connecting with the XMPP client

Getting ready

How to do it…

How it works…

There's more…

See also

Configuring the Ejabberd installation

Getting ready

How to do it…

How it works…

There's more…

See also

Creating web client with Strophe.js

Getting ready

How to do it…

How it works…

There's more…

See also

Enabling group chat

Getting ready

How to do it…

How it works…

There's more…

See also

Chat server with Node.js

Getting ready

How to do it…

How it works…

There's more…

See also

11. Git Hosting

Introduction

Installing Git

Getting ready

How to do it…

How it works…

There's more…

See also

Creating a local repository with Git CLI

Getting ready

How to do it…

How it works…

There's more…

See also

Storing file revisions with Git commit

Getting ready

How to do it…

How it works…

There's more…

Synchronizing the repository with a remote server

Getting ready

How to do it…

How it works…

There's more…

GitHub pages

See also

Receiving updates with Git pull

Getting ready

How to do it…

How it works…

See also

Creating repository clones

Getting ready

How to do it…

How it works…

See also

Installing GitLab, your own Git hosting

Getting ready

How to do it…

How it works…

There's more…

See also

Adding users to the GitLab server

Getting ready

How to do it…

Creating a repository with GitLab

Getting ready

How to do it…

Automating common tasks with Git hooks

Getting ready

How to do it…

How it works…

See also

12. Collaboration Tools

Introduction

Installing the VNC server

Getting ready

How to do it…

How it works…

See also

Installing Hackpad, a collaborative document editor

Getting ready

How to do it…

How it works…

There's more

Using Hackpad with Docker

See also

Installing Mattermost – a self-hosted slack alternative

Getting ready

How to do it…

How it works…

There's more …

See also

Installing OwnCloud, self-hosted cloud storage

Getting ready

How to do it…

How it works…

See also

13. Performance Monitoring

Introduction

Monitoring the CPU

Getting ready

How to do it…

How it works…

There's more…

See also

Monitoring memory and swap

Getting ready

How to do it…

How it works…

There's more…

See also

Monitoring the network

Getting ready

How to do it…

How it works…

There's more…

Monitoring storage

Getting ready

How to do it…

Setting performance benchmarks

Getting ready

How to do it…

There's more…

Graphing tools

More options

See also

14. Centralized Authentication Service

Introduction

Installing OpenLDAP

Getting ready

How to do it…

How it works…

See also

Installing phpLDAPadmin

Getting ready

How to do it…

How it works…

There's more…

See also

Ubuntu server logins with LDAP

Getting ready

How to do it…

How it works…

See also

Authenticating Ejabberd users with LDAP

Getting ready

How to do it…

How it works…

See also

Index

Ubuntu Server Cookbook

---

Ubuntu Server Cookbook

Copyright © 2016 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: June 2016

Production reference: 1270616

Published by Packt Publishing Ltd.

Livery Place

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Birmingham B3 2PB, UK.

ISBN 978-1-78588-306-4

www.packtpub.com

Credits

Author

Uday R. Sawant

Reviewer

Dominik Jakub Szynk

Commissioning Editor

Neil Alexander

Acquisition Editor

Divya Poojari

Content Development Editor

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Technical Editor

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Copy Editor

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Graphics

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Cover Work

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About the Author

Uday R. Sawant has completed his master's in computer applications from Mumbai University. He is skilled with more than four years of experience in software development and operations field.

He is an expert with the LAMP stack, JavaScript, and cloud infrastructure. Before starting as a software developer, he worked extensively with server hardware and has more than two years of experience as system administrator.

Currently, he is working as a software scientist in a Mumbai-based start-up called Sweet Couch. His responsibilities include developing backend services, setting up real-time communication server, and automating various daily tasks. With immense interest in machine learning, he likes to spend his spare time exploring this subject. His first book was Instant Building Multi-Page Forms with Yii How-To published by Packt Publishing.

I would like to thank Packt Publishing for giving me another opportunity to work with them and write my second book. A big thanks goes to my parents for their support throughout the time of writing this book. Also, I would like to thank my team at Sweet Couch as without their support, it would have not been possible to write a full length book. A special thanks to Mr. Mitul Thakkar who always encouraged me to keep on writing. Finally, thanks to Preeti Singh, an editor for this book, for keeping things on track.

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Preface

Welcome to Ubuntu Server Cookbook, a step-by-step guide to your own Ubuntu server.

Ubuntu is an open source operating system, or rather, I should say that Ubuntu is a mission to provide quality software to everybody without any cost. As mentioned on the official site, the meaning of the word Ubuntu is I am, cause we are and Ubuntu is working hard towards their mission by being more than just a free operating system.

Ubuntu is based on Debian, a well-established Linux distribution. However, Debian is kind of limited to geeks. Ubuntu added an easy user interface named Unity that made it popular with various desktop users. One answer on Ask Ubuntu compares Ubuntu and Debian to a local restaurant and a farmer, respectively. Ubuntu carefully selects the best things from Debian and adds its own flavors to make it easy and more enjoyable for the end users. It's still Debian at base, but it more easier to use and more stable with frequent updates and a definite release cycle.

Users can choose an Ubuntu operating system from nine different flavors, starting with lightweight desktop to a fully loaded multimedia editing system. In addition to desktop systems, Ubuntu provides separate editions for various server platforms, cloud systems, mobile devices, and tablets. The new versions are released every six months with a major release in April and updates in October. All security updates are released throughout the year, as and when necessary. Every new version released in an even year (2014, 2016, and so on) are tagged for Long Term Support (LTS). These versions receive extended support period of five years and are generally used in production environments.

At the time of writing, Ubuntu has already taken a major share in the server market and has already become a default choice of millions of cloud users. According to an article by Dustin Kirkland, a member of the product team at Canonical, November 2015 has seen over 2 million cloud instances being launched with Ubuntu Server. That's nearly one instance per second and these are just the numbers from cloud services. Ubuntu is being used in Desktop systems, laptops, mobiles, routers, and even to control your cars, drones, and countless Internet of Things (IoT) devices. Docker hub, a popular container repository reports more than 40 million pulls of official Ubuntu image.

The purpose of this book is to provide step-by-step solutions using the Ubuntu server. We will focus on common, server-related tasks such as user management, installing various packages for web servers, database, some low hanging fruits in performance and security, and many more. The book also covers the latest development in the container world with LXD and Docker. All recipes are based on the Ubuntu server, Xenial Xerus (version 16.04), the latest LTS release of Ubuntu.

What this book covers

The book is divided into multiple chapters, covering details of specific tasks.

Chapter 1, Managing Users and Groups, covers common user management tasks such as adding or removing user accounts, creating separate groups, assigning access rights, and setting user-level resource limits.

Chapter 2, Networking, explore the various network management functions, including network configuration, setting up DNS and DHCP servers, installing network proxy, and VPN setup. It also includes performance tuning tips and firewall setup.

Chapter 3, Working with Web Servers, provides a detailed configuration of web servers. This chapter covers both Apache and Nginx. You will also find some advance topics such as reverse proxy and load balancing using Nginx.

Chapter 4, Working with Mail Servers, explains the installation and configuration of your e-mail server.

Chapter 5, Handling Databases, discusses the popular relational database server, MySQL. It also covers MongoDB as a NoSQL database system, which is quite a hot technology in recent days.

Chapter 6, Network Storage, explains how to set up the good old Samba server along with FTP and Rsync details. Additionally, it includes the basics of NFS.

Chapter 7, Cloud Computing, includes details on virtualization with the Ubuntu server and some advance tools from Ubuntu to set up your own cloud system with OpenStack and Juju.

Chapter 8, Working with Containers, introduces Linux containers (LXC) and a container management tool by Ubuntu, LXD. This chapter also covers another hot topic, Docker.

Chapter 9, Streaming with Ampache, helps you to set up your own streaming server. We will take a quick look at Ampache, an open source web application for media streaming.

Chapter 10, Communication Server with XMPP, covers the installation of XMPP-based chat server, Ejabberd.

Chapter 11, Git Hosting, covers basic work flow of version control system Git and an open source web-based repository management tool GitLab.

Chapter 12, Collaboration Tools, explores more open source tools for your team and also covers the various tools to help your team stay connected.

Chapter 13, Performance Monitoring, introduces various monitoring tools that can help you optimize the performance of your Ubuntu server.

Chapter 14, Centralized Authentication Service, saves some efforts by introducing LDAP. This chapter covers the LDAP-based centralized authentication and authorization.

What you need for this book

The book is written with the help of Ubuntu server 16.04 and few virtual machines with VirtualBox. The recipes should work fine with Ubuntu version 14.04 and higher. For most of the recipes, a minimum hardware configuration of 512 MB memory with single CPU is enough. However, a few recipes such as OpenStack installation require additional hardware resources. The specific requirements are given in the respective recipes, if any.

Feel free to use any virtualization tool of your choice. Also, you can skip the local set up and use cloud servers. Many cloud providers give free introductory service for limited period. You can use these services to test your setup.

Who this book is for

Ubuntu Server Cookbook is intended for system administrators with a basic understanding of Linux operating system. If you are a software developer or a newbie system administrator and want to setup your own servers, this book is an ideal guide for you. You are not required to have an in-depth knowledge or hands-on experience with Ubuntu, but you should know the basic commands for directory navigation, file management, and file editing tool. An understanding of computer networks and Internet is advisable.

Sections

In this book, you will find several headings that appear frequently (Getting ready, How to do it…, How it works…, There's more…, and See also).

To give clear instructions on how to complete a recipe, we use these sections as follows:

Getting ready

This section tells you what to expect in the recipe, and describes how to set up any software or any preliminary settings required for the recipe.

How to do it…

This section contains the steps required to follow the recipe.

How it works…

This section usually consists of a detailed explanation of what happened in the previous section.

There's more…

This section consists of additional information about the recipe in order to make the reader more knowledgeable about the recipe.

See also

This section provides helpful links to other useful information for the recipe.

Conventions

In this book, you will find a number of text styles that distinguish between different kinds of information. Here are some examples of these styles and an explanation of their meaning.

Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows: You can check other log files like /var/log/mail.err and /var/log/upstart/dovecot.log

A block of code is set as follows:

disable_plaintext_auth = yes

Any command-line input or output is written as follows:

$ sudo adduser bob

New terms and important words are shown in bold. Words that you see on the screen, for example, in menus or dialog boxes, appear in the text like this: You can access the Inbox panel on port 7071.

Note

Warnings or important notes appear in a box like this.

Tip

Tips and tricks appear like this.

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Errata

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Questions

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Chapter 1. Managing Users and Groups

In this chapter, we will cover the following recipes:

Creating a user account

Creating user accounts in batch mode

Creating a group

Adding group members

Deleting a user account

Managing file permissions

Getting root privileges with sudo

Setting resource limits with limits.conf

Setting up public key authentication

Securing user accounts

Introduction

In this chapter, you will see how to add new users to the Ubuntu server, update existing users, and set permissions for users. You will get to know the default setting for new users and how to change them. Also, you will take a look at secure shell (SSH) access and securing user profiles.

Creating a user account

While installing Ubuntu, we add a primary user account on the server; if you are using the cloud image, it comes preinstalled with the default user. This single user is enough to get all tasks done in Ubuntu. There are times when you need to create more restrictive user accounts. This recipe shows how to add a new user to the Ubuntu server.

Getting ready

You will need super user or root privileges to add a new user to the Ubuntu server.

How to do it…

Follow these steps to create the new user account:

To add a new user in Ubuntu, enter following command in your shell:

$ sudo adduser bob

Enter your password to complete the command with sudo privileges:

Now enter a password for the new user:

Confirm the password for the new user:

Enter the full name and other information about the new user; you can skip this part by pressing the Enter key.

Enter Y to confirm that information is correct:

This should have added new user to the system. You can confirm this by viewing the file /etc/passwd:

How it works…

In Linux systems, the adduser command is higher level command to quickly add a new user to the system. Since adduser requires root privileges, we need to use sudo along with the command, adduser completes following operations:

Adds a new user.

Adds a new default group with the same name as the user.

Chooses UID (user ID) and GID (group ID) conforming to the Debian policy.

Creates a home directory with skeletal configuration (template) from /etc/skel.

Creates a password for the new user.

Runs the user script, if any.

If you want to skip the password prompt and finger information while adding the new user, use the following command:

$ sudo adduser --disabled-password --gecos username

Alternatively, you can use the useradd command as follows:

$ sudo useradd -s -m -d -g UserName

Where:

-s specifies