CentOS High Performance

Gabriel Canepa

• Publisher: Packt Publishing
• Year: 2016
• ISBN:
  9781785288685
• Edition: 1
• Topic: Computer Science
• Subtopic: Operating Systems
• Index: Computer Science

Create high availability clusters to enhance system performance using CentOS 7

About This Book

• Master the concepts of high performance and high availability to eliminate performance bottlenecks
• Maximize the uptime of services running in a CentOS 7 cluster
• A step-by-step guide that will provide knowledge of methods and approaches to optimize the performance of CentOS clusters

Who This Book Is For

This book is targeted at system administrators: those who want a detailed, step-by-step guide to learn how to set up a high-availability CentOS 7 cluster, and those who are looking for a reference book to help them learn or refresh the necessary skills to ensure their systems and respective resources are utilized optimally. No previous knowledge of high-availability systems is needed, though the reader is expected to have at least some degree of familiarity with any spin-off of the Fedora family of Linux distributions, preferably CentOS.

What You Will Learn

• Install a CentOS 7 cluster and network infrastructure
• Configure firewall, networking, and clustering services and settings
• Set up and test a HAC (high-availability cluster) to host an Apache web server and a MariaDB database server
• Monitor performance and availability
• Identify bottlenecks and troubleshoot issues
• Improve performance and ensure high availability

In Detail

CentOS is the enterprise level Linux OS, which is 100% binary compatible to Red Hat Enterprise Linux (RHEL). It acts as a free alternative to RedHat's commercial Linux offering, with only a change in the branding. A high performance cluster consists in a group of computers that work together as one set parallel, hence minimizing or eliminating the downtime of critical services and enhancing the performance of the application.

Starting with the basic principles of clustering, you will learn the necessary steps to install a cluster with two CentOS 7 servers. We will then set up and configure the basic required network infrastructure and clustering services. Further, you will learn how to take a proactive approach to the split-brain issue by configuring the failover and fencing of the cluster as a whole and the quorum of each node individually. Further, we will be setting up HAC and HPC clusters as a web server and a database server. You will also master the art of monitoring performance and availability, identifying bottlenecks, and exploring troubleshooting techniques.

At the end of the book, you'll review performance-tuning techniques for the recently installed cluster, test performance using a payload simulation, and learn the necessary skills to ensure that the systems, and the corresponding resources and services, are being utilized to their best capacity.

Style and approach

An easy-to-follow and step-by-step guide with hands-on instructions to set up real-world simple cluster scenarios that will start you on the path to building more complex applications on your own.

CentOS High Performance

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Table of Contents

CentOS High Performance

Credits

About the Author

About the Reviewers

www.PacktPub.com

Support files, eBooks, discount offers, and more

Why subscribe?

Free access for Packt account holders

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Errata

Piracy

Questions

1. Cluster Basics and Installation on CentOS 7

Clustering fundamentals

Why Linux and CentOS 7?

Downloading CentOS

Setting up CentOS 7 nodes

Installing CentOS 7

Setting up the network infrastructure

Installing the packages required for clustering

Key software components

Setting up key-based authentication for SSH access

Summary

2. Installing Cluster Services and Configuring Network Components

Configuring and starting clustering services

Starting and enabling clustering services

Troubleshooting

Security fundamentals

Letting in and letting out

Getting acquainted with PCS

Managing authentication and creating the cluster

Setting up a virtual IP for the cluster

Adding a virtual IP as a cluster resource

Viewing the status of the virtual IP

Summary

3. A Closer Look at High Availability

Failover – an introduction to high availability and performance

Fencing – isolating the malfunctioning nodes

Installing and configuring a STONITH device

Split-brain – preparing to avoid inconsistencies

Quorum – scoring inside your cluster

Configuring our cluster with PCS GUI

Summary

4. Real-world Implementations of Clustering

Setting up storage

ELRepo repository and DRBD availability

Configuring DRBD

Adding DRBD as a PCS cluster resource

Installing the web and database servers

Configuring the web server as a cluster resource

Mounting the DRBD resource and using it with Apache

Testing the DRBD resource along with Apache

Setting up a high-availability database with replicated storage

Troubleshooting

Summary

5. Monitoring the Cluster Health

Cluster services and performance

Monitoring the node status

Monitoring the resources

When a resource refuses to start

Checking the availability of core components

Summary

6. Measuring and Increasing Performance

Setting up a sample database

Downloading and installing the Employees database

Introducing initial cluster tests

Test 1 – retrieving all fields from all records

Test 2 – performing JOIN operations

Performing a failover

Measuring and improving performance

Apache's configuration and settings

Loading and disabling modules

Placing limits on the number of Apache processes and children

Database resource

Creating indexes

Using query cache

Moving to an A/A cluster

Summary

Index

CentOS High Performance

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: January 2016

Production reference: 1250116

Published by Packt Publishing Ltd.

Livery Place

35 Livery Street

Birmingham B3 2PB, UK.

ISBN 978-1-78528-868-5

www.packtpub.com

Credits

Author

Gabriel Cánepa

Reviewers

Muhammad Kamran Azeem

Denis Fateyev

Lekshminarayanan K

Oliver Pelz

Commissioning Editor

Veena Pagare

Acquisition Editor

Subho Gupta

Content Development Editor

Zeeyan Pinheiro

Technical Editor

Vivek Pala

Copy Editor

Pranjali Chury

Project Coordinator

Suzanne Coutinho

Proofreader

Safis Editing

Indexer

Mariammal Chettiyar

Graphics

Disha Haria

Production Coordinator

Nilesh Mohite

Cover Work

Nilesh Mohite

About the Author

Gabriel Cánepa is a Linux Foundation certified system administrator (LFCS-1500-0576-0100) and web developer from Villa Mercedes, San Luis, Argentina. He works for a worldwide leading consumer product company and takes great pleasure in using FOSS tools to increase productivity in all areas of his daily work. When he's not typing commands or writing code or articles, he enjoys telling bedtime stories with his wife to his two little daughters and playing with them, which is a great pleasure in his life.

I would like to thank God for the many blessings and the growth opportunities in personal, family, and professional life that He has given throughout my life.

I would like to thank my mother, who always encouraged me to get as much education as possible and to excel in everything I do. I'd also like to thank my wife, Monica, and our two daughters, Camila and Francesca, for their support, understanding, and patience during the long hours of troubleshooting and writing this book.

Next, I'd like to thank Andrea de Ampalio and Diego Cordoba from Carrera Linux Argentina (www.carreralinux.com.ar), who helped me learn and love Linux in the best Linux training academy—t...

Table of contents

• CentOS High Performance