HAProxy is free, open source software that provides a high availability load balancer and proxy server for TCP and HTTP-based applications that spreads requests across multiple servers.It is written in C and has a reputation for being fast and efficient (in terms of processor and memory usage).
HAProxy is used by a number of high-profile websites including GoDaddy, GitHub, Bitbucket, Stack Overflow, Reddit, Slack, Speedtest.net, Tumblr, Twitter and Tuenti and is used in the OpsWorks product from Amazon Web Services.
Examples of configurations are included in the example file(example haproxy for run docker and balance 3 web server), which is the corresponding docker file
