There is a range of solutions. The problem is that you need to choose the most suitable for you. Here briefly are painted options postgresql.leopard.in.ua/html
The customer had specific requirements. He had to make the decision worked in docker swarm.
Considered RepMgr, Patroni, Stolon. Liked https://github.com/sorintlab/stolon.
The floor of the flight base is 30 gig. about 50 users. The normal flight.