upstream backend {
    server web1:80;
    server web2:80;
    server web3:80;
}

server {
    listen 80;
    server_name localhost;
    
    location / {
        proxy_pass http://backend;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}