What are the benefits of using HAProxy?

This setup simplifies a number of things:

• All applications access the cluster via one single IP. The topology of the database cluster is masked behind HAProxy.
• MySQL Connections are load-balanced between available DB nodes
• It is possible to add or remove database nodes without any changes to the applications.
• Once the max number of database connections (in MySQL) is reached, HAProxy queues additional new connections. This is a neat way of throttling database connection requests and achieves overload protection.