Book Image

PostgreSQL 12 High Availability Cookbook - Third Edition

By : Shaun Thomas
Book Image

PostgreSQL 12 High Availability Cookbook - Third Edition

By: Shaun Thomas

Overview of this book

Databases are nothing without the data they store. In the event of an outage or technical catastrophe, immediate recovery is essential. This updated edition ensures that you will learn the important concepts related to node architecture design, as well as techniques such as using repmgr for failover automation. From cluster layout and hardware selection to software stacks and horizontal scalability, this PostgreSQL cookbook will help you build a PostgreSQL cluster that will survive crashes, resist data corruption, and grow smoothly with customer demand. You’ll start by understanding how to plan a PostgreSQL database architecture that is resistant to outages and scalable, as it is the scaffolding on which everything rests. With the bedrock established, you'll cover the topics that PostgreSQL database administrators need to know to manage a highly available cluster. This includes configuration, troubleshooting, monitoring and alerting, backups through proxies, failover automation, and other considerations that are essential for a healthy PostgreSQL cluster. Later, you’ll learn to use multi-master replication to maximize server availability. Later chapters will guide you through managing major version upgrades without downtime. By the end of this book, you’ll have learned how to build an efficient and adaptive PostgreSQL 12 database cluster.
Table of Contents (17 chapters)

Setting up pglogical

PostgreSQL 9.4 introduced a feature called replication slots. This essentially makes it possible to decode the transaction log and extract database write traffic for remote replay at a logical level. Unlike standard replication, which requires the primary and replica to be identical, slots can be mined for specific information relevant to user needs.

One of the first PostgreSQL extensions to make use of replication slots is pglogical by 2ndQuadrant. Like Slony and Bucardo, pglogical can copy individual tables from one database to another. Unlike those other pieces of software, it does so without encumbering tables with performance-robbing triggers and does not rely on an external daemon to coordinate data copy streams.

This recipe will explain how to install and configure pglogical for easy table copies.

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