Comment by hitpointdrew

The best way I have found is to setup keepalived -> pgbouncer -> Postgres. Use repmgr to manage replication and barman for backups. Setup a VIP with keepalived with a small script that checks if the server is primary. You loose about 7-9 pings during a failover, have keepalived check about every 2 seconds and flip after 3 consecutive failures.