Book Image

PostgreSQL 9 High Availability Cookbook

By : Shaun Thomas
Book Image

PostgreSQL 9 High Availability Cookbook

By: Shaun Thomas

Overview of this book

A comprehensive series of dependable recipes to design, build, and implement a PostgreSQL server architecture free of common pitfalls that can operate for years to come. Each chapter is packed with instructions and examples to simplify even highly complex database operations. If you are a PostgreSQL DBA working on Linux systems who want a database that never gives up, this book is for you. If you've ever experienced a database outage, restored from a backup, spent hours trying to repair a malfunctioning cluster, or simply want to guarantee system stability, this book is definitely for you.
Table of Contents (12 chapters)
11
Index

Adding DRBD to cluster management

DRBD is actually one of the most difficult resources to manage with Pacemaker. Unlike a regular service that is started or stopped depending on where it is active, DRBD is always active. The only thing that changes between two nodes running DRBD is the Primary or Secondary state ascribed to each.

Due to this complication, DRBD is not one resource, but two:

  • A DRBD resource to manage starting and stopping DRBD
  • A master/slave resource to control which node acts as the Primary

In this recipe, we'll allocate both of these resources so that Pacemaker can manage DRBD properly.

Getting ready

As we're continuing to configure Pacemaker, make sure you've followed all previous recipes.

How to do it...

In the previous chapter, we created a DRBD resource named pg. With this in mind, follow these steps as the root user to add DRBD to Pacemaker:

  1. Create a basic Pacemaker primitive for DRBD with this command:
    crm configure primitive drbd_pg ocf:linbit:drbd \
        params...