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

Measuring and improving performance

You will recall from earlier chapters that by definition, a resource is a service that is made highly available by the cluster. Every resource is assigned what is called a resource agent, an external shell script that manages the actual resource for the cluster, independently of how those services would be managed by systemd if they were left to its care. Thus, the actual operation of the resource is transparent to the cluster, since it is being managed by the resource agent.

Resource agents are found inside /usr/lib/ocf/resource.d, so feel free to take a look at them to become better acquainted with their structure. In most circumstances, you will not need to modify them, but work on the specific resources' configuration files, as we shall see. You will recall from earlier chapters that adding a cluster resource involved using an argument of the standard:provider:resource_agent form (ocf:heartbeat:mysql, for example).You can also view the complete list...