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 LVM to cluster management

To avoid potential conflicts, we will continue to add resources to Pacemaker in the same order as if we were starting them manually. After DRBD comes our second LVM layer. The primary purpose of Pacemaker in this instance is to activate or deactivate the VG_POSTGRES volume group that we created in the previous chapter.

This is necessary because DRBD can not demote a primary resource to secondary status as long as there are any open locks. Any LVM volume group that contains active volumes can cause these kind of locks. Also, we cannot utilize a volume group that has no active volumes when DRBD is promoted on the second node.

This recipe will explain the steps necessary to manage our VG_POSTGRES/LV_DATA data volume with Pacemaker.

Getting ready

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

Tip

Debian-derivative systems such as Ubuntu need to beware! To avoid potential issues, immediately delete the /lib...