PostgreSQL 12 High Availability Cookbook - Third Edition

Configuring HAProxy to load balance PostgreSQL

Given that we're attempting to build a highly available cluster of PostgreSQL nodes, it's very likely we'll have a veritable horde of replicas for various purposes. Some will exist as dedicated standby nodes, one may be a quorum witness, others could be remote disaster-recovery alternates, and so on.

It would be a shame if all of these resources were not utilized in some manner. We've bought multiple servers, and strategically placed them in important locations while taking their dedicated roles into consideration.

Perhaps more importantly, not every application requires the ability to write to the database. Interactive applications are far more likely to present information obtained from the ...