How to set up a cluster for a ruby ​​on rails application?

Question

PostgreSQL

How to set up a failover cluster for a ruby ​​on rails site?

Answer 1

Applications of medium load / fault tolerance:
1 - Balancer: at the input 80, 443, install the nginx / haproxy balancer (2 servers + amazon route 53 or an analogue with a check for the availability of the host dns ttl 5 min)
2 - app worker - servers (thin, passenger, puma, etc.) with your ruby ​​application (2+ servers)
3 - DB - postgresql: 2+ master/slave servers, wal sync out of the box.