Setting up Postgres Automated Failover
Nowadays, failover is one of the simplest procedures in postgres. Still, there are not many ways to automate this procedure and perform it without any human interference. This blog post will guide you through a way to implement automated failover by using two open source projects, repmgr2 and pgbouncer . PGbouncer will act like a connection pool and as an entry point to the database cluster. Repmgr now, (since version 2) supports automatic failover, the slave will try to connect to the master for a predefined time and number of attempts, if it fails, it will run a script that can be anything. We are going to use this functionality to perform auto-failover, redirect our application connections to the new master database, and notify the dba that a failover has been performed. Each server will have its own copy of pgbouncer configuration file(s) and when a server is being promoted, the new master also has the responsibility to overwrite the configuration file on the server that