Book Image

CentOS High Performance

By : Gabriel Cánepa
Book Image

CentOS High Performance

By: Gabriel Cánepa

Overview of this book

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.
Table of Contents (13 chapters)
CentOS High Performance
About the Author
About the Reviewers

Failover – an introduction to high availability and performance

The failover process can be roughly described as the action of switching, in the event of power or network failure, to an available resource to resume operations with the least downtime as possible, with no downtime being the primary goal of high availability clusters.

In Chapter 2, Installing Cluster Services and Configuring Network Components, we configured a simple but essential resource for our purposes: a virtual IP address. You will also recall that in order to start becoming acquainted with PCS—the tool that is used as a frontend to PCS (the configuration manager)—we presented a brief introduction to its basic syntax and usage.


As in other cases in the Linux ecosystem, the program/protocol/package name is written in caps, while the tool and utility is written in lowercase. Thus, PCS is used to indicate the package name, and it is the command-line utility that is used to manage PCS.

With the pcs status command, we will...