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

Configuring DRBD

After having successfully created and partitioned our DRBD disks on each node, the main configuration file for DRBD is located in /etc/drbd.conf, which consists only of the following two lines:

include "drbd.d/global_common.conf";
include "drbd.d/*.res";

Both lines include relative paths, starting at /etc/, of the actual configuration files. In the global_common.conf file, you will find the global settings for your DRBD installation, along with the common section (which defines those settings that should be inherited by every resource) of the DRBD configuration. On the other hand, in the .res files, you will find the specific configuration for each DRBD resource.

We will now rename the existing global_common.conf file as global_common.conf.orig (as a backup copy of the original settings) with the following command:

mv /etc/drbd.d/global_common.conf /etc/drbd.d/global_common.conf.orig

We will then create a new global_common.conf file with the following contents by opening the...