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

Security fundamentals

At this point, we are ready to discuss network security to only allow the proper network traffic between the nodes. During the initial setup and while performing your first tests, you may want to disable the firewall and SELinux (which is described later in this chapter) and then go through both of them at a later stage—it is up to you depending on your grade of familiarity with them at this point.

Letting in and letting out

After having started and enabled the services mentioned earlier, we are ready to take a closer look at the network processes involved in the cluster configuration and maintenance. With the help of the netstat command, a tool included in the net-tools package for CentOS 7, we will print the current listening network ports and verify that corosync is running and listening for connections. Before doing so, you will need to install the net-tools package, as it is not included in the minimal CentOS 7 setup, using the following command:

yum –y install net...