Nginx Load Balancer Configuration

Nginx's upstream module turns it into a powerful software load balancer. Define your backend pool, pick a balancing strategy, and let our generator build the config block for you.

An upstream block

List the backends in an upstream and proxy_pass to it. Round-robin is the default.

upstream app {
    least_conn;
    server 10.0.0.1:8080;
    server 10.0.0.2:8080;
}
server {
    location / { proxy_pass http://app; }
}

Choosing a method

round-robin spreads requests evenly, least_conn favors the backend with fewest active connections, and ip_hash pins a client to one backend, which helps when sessions are stored locally.

Open the Load balancer generator

Frequently asked questions

Does open-source Nginx do active health checks?

No. It marks a server failed passively via max_fails and fail_timeout. Active health checks need Nginx Plus or an external checker.

How do I take a backend out of rotation?

Add the down parameter to its server line and reload Nginx.

Guides

• Nginx Reverse Proxy Configuration
• Caddy Reverse Proxy Configuration
• Nginx Static Site Configuration
• Caddy Static Site Configuration
• Nginx + PHP-FPM Configuration
• Caddy + PHP-FPM Configuration
• Nginx SSL/TLS Configuration
• Nginx Load Balancer Configuration
• Caddy Load Balancer Configuration
• Nginx Rate Limiting Configuration
• Nginx Security Headers Configuration
• Caddy Security Headers Configuration
• Nginx Gzip Compression Configuration
• Nginx Caching Configuration
• Caddy HTTPS Redirect Configuration
• Nginx WebSocket Proxy Configuration
• Nginx Content-Security-Policy Header
• Block Bad Bots and Scanners in Nginx
• fail2ban for Nginx
• nginx.conf Best Practices
• Nginx Location Regex Tester
• Deploy Nginx Config with GitHub Actions
• Nginx CORS Headers Configuration
• Nginx Cache-Control Headers Configuration
• Nginx 301 Redirect Map Configuration
• robots.txt, Sitemap and security.txt
• Apache .htaccess Configuration
• Docker Compose and Dockerfile Configuration
• systemd Service and Timer Configuration
• Cron Expression Explainer
• SSH Hardening with sshd_config
• Linux Firewall Rules: ufw, nftables and iptables
• Glob Pattern Tester
• Analysing Nginx Access Logs with awk
• Subnet Mask and CIDR Calculator
• VLAN Configuration on Linux
• Static Routes and Policy Routing on Linux
• NAT and Port Forwarding with nftables
• DHCP Server Configuration
• BIND Zone File Example
• WireGuard Server and Client Configuration
• A Simple IP Plan for Your Home Network