Book Image

PostgreSQL High Availability Cookbook - Second Edition

By : Shaun Thomas
Book Image

PostgreSQL High Availability Cookbook - Second Edition

By: Shaun Thomas

Overview of this book

Databases are nothing without the data they store. In the event of a failure - catastrophic or otherwise - immediate recovery is essential. By carefully combining multiple servers, it’s even possible to hide the fact a failure occurred at all. From hardware selection to software stacks and horizontal scalability, this book will help you build a versatile PostgreSQL cluster that will survive crashes, resist data corruption, and grow smoothly with customer demand. It all begins with hardware selection for the skeleton of an efficient PostgreSQL database cluster. Then it’s on to preventing downtime as well as troubleshooting some real life problems that administrators commonly face. Next, we add database monitoring to the stack, using collectd, Nagios, and Graphite. And no stack is complete without replication using multiple internal and external tools, including the newly released pglogical extension. Pacemaker or Raft consensus tools are the final piece to grant the cluster the ability to heal itself. We even round off by tackling the complex problem of data scalability. This book exploits many new features introduced in PostgreSQL 9.6 to make the database more efficient and adaptive, and most importantly, keep it running.
Table of Contents (18 chapters)
Title Page
About the Author
About the Reviewer
Customer Feedback

Installing and configuring Nagios

Nagios is a well-known monitoring tool. We won't make any claims that it is the best or most suitable tool for watching a highly available PostgreSQL installation. However, the community is large, the functionality is extensive and established, and interoperability with other tools and libraries is high.

As an unfortunate consequence, the amount of installation prerequisites is rather lengthy. To get Nagios working properly, we need an HTTP server, Perl, and a mail daemon. Some plugins require PHP, while others need MySQL, SNMP, or any number of esoteric utilities and acronyms. There might be DBAs who also have strong skills as webmasters, but we can't depend on that. Getting Nagios installed with all of its foundation services is very complex, so we don't recommend that you do so.

Due to its history, the likelihood that Nagios is available on major Linux distributions is very high. Installing Nagios through the distribution will handle most, if not all, configuration...