haproxy

HAProxy is a free, open source high availability solution, providing load balancing and proxying for TCP and HTTP-based applications by spreading requests across multiple servers.

docker-compose.yml

haproxy:
  image: haproxy:alpine
  volumes:
    - ./haproxy.cfg:/usr/local/etc/haproxy/haproxy.cfg
  net: host
  restart: always

haproxy.cfg

This sample config shows you how to setup a simple tcp load balancer.

#                       +- jp (:1081)
#                       |
#                       |- tw (:1082)
# frontend --- backend -+  
# (*:1080)              |- hk (:1083)
#                       |
#                       +- us (:1084)

global
        # daemon # WARNING: DO NOT USE IT!
        maxconn 4000

defaults
        mode tcp
        timeout connect 5000ms
        timeout client 50000ms
        timeout server 50000ms

frontend front
        bind *:1080
        default_backend back

backend back
        balance roundrobin
        server jp 127.0.0.1:1081 weight 50
        server tw 127.0.0.1:1082 weight 20
        server hk 127.0.0.1:1083 weight 15
        server us 127.0.0.1:1084 weight 15

⚠️ haproxy must not be daemonized!