How to Set Up HAProxy Load Balancing for Two Nginx Servers

Prerequisites

1. Install HAProxy.

2. Start two web application servers, here two Nginx instances.

Nginx1 on port 8080, Nginx2 on port 8081. Both serve a test.html page with different content (1 on nginx1, 2 on nginx2).

Goal

Configure HAProxy as a front‑end load balancer so that accessing test.html through HAProxy dynamically routes to nginx1 or nginx2, displaying 1 or 2. Refreshing the page multiple times should show alternating outputs.

Configuration File

Create a conf directory under HAProxy’s installation path and add haproxy.cfg with the following content:

global
    daemon
    maxconn 256

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

frontend http-in
    bind *:7000
    default_backend neo4j

backend neo4j
    server s1 127.0.0.1:8080 maxconn 32
    server s2 127.0.0.1:8081 maxconn 32

listen admin
    bind *:7080
    stats enable

Explanation:

frontend http‑in : listens on port 7000.

server s1 and server s2 : define the two backend servers and their ports.

Start HAProxy with:

/usr/local/haproxy/sbin/haproxy -f /usr/local/haproxy/conf/haproxy.cfg

Testing

Visit http://<em>server_address</em>:7000/test.html. Refresh the page repeatedly; the output should alternate between 1 and 2, confirming that HAProxy is correctly distributing requests.