HAProxyのコンフィグファイルの一例です。

haproxy.cfg

# Global
global
  daemon

# Defaults
defaults
  mode tcp
  timeout connect 5s
  timeout client 10s
  timeout server 10s
  retries 2

# REDIS
frontend redis
  bind *:6379
  default_backend redis_backend

backend redis_backend
  option tcp-check
  tcp-check connect
  tcp-check send PING\r\n
  tcp-check expect string +PONG
  tcp-check send info\ replication\r\n
  tcp-check expect string role:master
  tcp-check send QUIT\r\n
  tcp-check expect string +OK
  server redis1 127.0.0.1:6380 check inter 1s
  server redis2 127.0.0.1:6381 check inter 1s

# Elasticsearch
frontend elasticsearch
  bind *:9200
  default_backend elasticsearch_backend

backend elasticsearch_backend
  balance first
  option redispatch
  retries 2
  server elasticsearch1 127.0.0.1:9201 check inter 1s
  server elasticsearch2 127.0.0.1:9202 check inter 1s
  server elasticsearch3 127.0.0.1:9203 check inter 1s