PostgreSQL 12 High Availability Cookbook - Third Edition

How it works...

Modern servers are often equipped with hardware that enables remote administration. These components often allow network access to the boot process itself. In the case where PostgreSQL is installed on virtual servers, the hypervisor serves this role. Many companies commonly install Power Distribution Units (PDU) that can be remotely instructed to cut power to a server.

Whatever the approach, working with infrastructure or systems operations teams is likely necessary to gain access to interact with these devices. As an example, imagine we have a 2-node cluster consisting of a Primary and Standby, and a PDU is available for each. We could do something like this:

In this case, in the case of a failover and subsequent promotion, ...