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)

Understanding our chosen filesystem components

Presuming that we have all of the hardware and software we discussed earlier, our servers are still missing the following three things:

  • The ability to synchronize data to two servers simultaneously
  • The capacity to freeze data to prevent changes for backup purposes
  • A durable filesystem designed for multiprocessing I/O

There are several solutions for each of these missing elements, yet we've settled on three in particular: DRBD, LVM, and XFS. Let's explore a bit about each of these technologies and discuss why we've chosen them for mirroring data at the server level.

Why DRBD?

DRBD stands for Distributed Replicated Block Device. DRBD is meant to operate below the...