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


One element that is absolutely required for any highly available PostgreSQL installation is replication. It does not matter if we have a Storage Area Network (SAN) that provides disk redundancy, nor is DRBD or other block-level replication sufficient to protect our investment. Duplicating and backing up data is always a good practice, but when it comes to availability, we need online copies of the database.

Similarly, if other departments need data that resides in our OLTP database, how can we provide it safely? In ideal circumstances, we can supply a copy of the necessary tables. This way, we don't strain the primary database with ad hoc report-based queries. A new DBA might try to accomplish this by building a synchronization library or performing scheduled extracts and copies into a remote database. However, there are easier ways!

PostgreSQL gives us methods to build and maintain a fully online copy of our primary database. Furthermore, there are existing utilities to duplicate...