Nginx Configuration Guide: HTTP Server, Static Files, Reverse Proxy, Load Balancing and Advanced Directives

The article, authored by a senior architect, provides a step‑by‑step tutorial on using Nginx for multiple roles, including serving static resources, acting as a reverse proxy, and performing load balancing.

1. HTTP Server – Nginx can serve static files directly. Create a document root (e.g., Docroot(/usr/local/var/www)) and place an index.html or other files under an html directory. A minimal nginx.conf server block looks like:

user  nginx;
http {
    server {
        listen       80;
        server_name  localhost;
        location / {
            root   /usr/local/var/www/html;
            index  index.html index.htm;
        }
    }
}

Accessing http://localhost/ returns the default Nginx page, while http://localhost/test.html maps to /usr/local/var/www/html/test.html.

2. Static Server – Create separate directories (e.g., /usr/local/var/www/images and /usr/local/var/www/img) and place test images. Use the set directive to define a variable $doc_root and map locations:

http {
    server {
        listen 80;
        server_name localhost;
        set $doc_root /usr/local/var/www;
        location / {
            root   $doc_root/html;
            index  index.html index.htm;
        }
        location ^~ /images/ {
            root $doc_root;
        }
        location ~* \.(gif|jpg|jpeg|png|bmp|ico|swf|css|js)$ {
            root $doc_root/img;
        }
    }
}

This demonstrates path‑based and suffix‑based location matching.

3. Location Matching & Priority – Nginx supports several location modifiers ( =, ^~, ~, ~*, plain prefix). The priority order is: location = / (exact match) location ^~ /path/ (prefix, stop search) location ~ /regex/ and ~* (regex, longest wins)

plain prefix locations location / (catch‑all)

Example configuration illustrating these rules is provided in the source.

4. Reverse Proxy – The most common Nginx use‑case. A request is received by Nginx and forwarded to an internal service using proxy_pass. Example:

server {
    listen 80;
    server_name localhost;
    location / {
        proxy_pass http://localhost:8081;
        proxy_set_header Host $host:$server_port;
        proxy_set_header X-Forwarded-For $remote_addr;
        proxy_next_upstream error timeout invalid_header http_500 http_502 http_503;
    }
}

Visiting http://localhost/ actually reaches the backend at localhost:8081.

5. Load Balancing – Defined with the upstream block. Nginx supports several built‑in strategies:

Round‑robin (default)

Weighted round‑robin ( weight parameter) ip_hash – sticky sessions based on client IP

Third‑party fair – selects the server with the lowest response time

Third‑party url_hash – hashes the request URI

Example of weighted load balancing:

upstream test {
    server localhost:8081 weight=1;
    server localhost:8082 weight=3;
    server localhost:8083 weight=4 backup;
}

Requests are distributed according to the defined weights, with the backup server used only if the primary servers fail.

6. Additional Useful Directives return – sends a status code and optional redirect URL. rewrite – modifies the request URI using regular expressions. error_page – custom error pages.

Logging configuration with log_format and access_log, optionally enabling gzip on for compression. deny – blocks access to specific file types or paths.

Built‑in variables (e.g., $host, $remote_addr, $request_uri, $scheme) can be used throughout the configuration.

The article concludes with a reminder to like and share, and provides links to additional resources and community groups.