How is an Nginx configuration structured?

Most settings have a defined context. Putting a directive in the wrong place is a common reason a config fails to start. The hierarchy also explains inheritance: a setting in http applies to every server and location below it until overridden.

user nginx;
worker_processes auto;

events {
    worker_connections 4096;
}

http {
    include /etc/nginx/mime.types;
    sendfile on;
    keepalive_timeout 65;

    server {
        listen 80;
        server_name example.com;
        root /var/www/site;

        location / {
            try_files $uri $uri/ =404;
        }
    }
}

Context rules

• main holds process-wide directives such as user, worker_processes and pid
• events controls connection acceptance and worker connection limits
• http groups all HTTP servers, MIME types, logging and shared zones
• server represents a virtual host; location selects a URI prefix or pattern
• include splices another file into the current context