Managing streaming replication

In this section, we will talk about why we have to have replicas.

Figure 17.1: Primary/Replica Schema

In a production environment, you often need to be able to restore it as quickly as possible after a system crash. In order to do this, we have to use the streaming replication technique. To make this possible, we need at least two servers, one primary server and one secondary server. The primary server performs all the operations that will be requested by the application programs; the replica server will be available only for read operations and will have the data copied in real time.

Basic concepts of streaming replication

The idea behind streaming replication is to copy the WAL files from the primary server to another (replica) server.

The replica server will be in a state of continuous recovery, and it continuously executes the WAL that is passed by the primary machine; this way, the replica machine binarily replicates the...