HAProxy

Why HAProxy?

Feature	HAProxy	Nginx	Traefik
Performance	Highest	High	Medium
Stats Dashboard	✅	❌	✅
Connection Pooling	✅ Advanced	Basic	Basic
Best For	High traffic	General	Microservices

haproxy.cfg

global
    log /dev/log local0
    chroot /var/lib/haproxy
    stats socket /run/haproxy/admin.sock mode 660 level admin
    user haproxy
    group haproxy
    daemon

defaults
    log     global
    mode    http
    option  httplog
    timeout connect 5000
    timeout client  50000
    timeout server  50000

# Frontend (HTTP → HTTPS redirect)
frontend http_front
    bind *:80
    redirect scheme https code 301 if !{ ssl_fc }

# Frontend (HTTPS)
frontend https_front
    bind *:443 ssl crt /etc/haproxy/certs/snapcode.pem
    default_backend snapcode_backend

# Backend (Load Balancing)
backend snapcode_backend
    balance roundrobin
    option httpchk GET /
    http-check expect status 200

    server snapcode1 localhost:8000 check weight=3
    server snapcode2 localhost:8001 check weight=2
    server snapcode3 localhost:8002 check weight=1
    server snapcode4 localhost:8003 check backup

    http-reuse safe

# Stats Page
listen stats
    bind *:8404
    stats enable
    stats uri /stats
    stats refresh 30s
    stats auth admin:password

Quick Start

sudo apt install haproxy
sudo cp haproxy.cfg /etc/haproxy/
sudo systemctl restart haproxy

# View stats
http://your-server:8404/stats

Load Balancing Strategies

Strategy	Use Case
roundrobin	Default, equal distribution
leastconn	Long-lived connections
source	Sticky sessions (IP hash)