Nginx Tutorial
NGINX Directives
NGINX directives provide instructions to control the behavior of NGINX and customize its functionality. Following are the reasons why NGINX directives are necessary:
- Server Configuration: NGINX directives allow you to define server-level settings such as the server name, port, SSL certificates, and default behavior for handling requests.
- Location-based Routing: Directives like location enable you to specify rules for handling requests based on the requested URL. You can configure different behaviors for specific URLs or URL patterns, such as proxying requests to backend servers or serving static files.
- Load Balancing: NGINX directives like upstream and proxy_pass are used to set up load balancing and distribute incoming traffic across multiple backend servers. This improves the performance, scalability, and availability of your application.
- Caching: NGINX supports directives like proxy_cache and fastcgi_cache to enable caching of responses from backend servers. Caching helps reduce the load on backend servers and improves the response time for subsequent requests.
- Security: NGINX directives allow you to enforce security measures such as SSL/TLS encryption (ssl_* directives), enabling HTTP/2 (http2 directive), restricting access based on IP addresses (allow and deny directives), or setting up authentication and authorization.
- Request and Response Modification: NGINX directives like rewrite, add_header, and proxy_set_header provide ways to modify incoming requests or outgoing responses. You can rewrite URLs, add custom headers, modify request headers, or handle redirects.
- Performance Optimization: NGINX directives offer various performance optimization techniques. For example, you can enable gzip compression (gzip directive) to reduce the size of responses, adjust buffer sizes (client_body_buffer_size and client_max_body_size directives), or fine-tune timeouts to improve the overall performance of your web server.
Commonly used Nginx directives
| Directive | Description |
| worker_processes | Sets the number of worker processes that Nginx should create |
| events | Configures event processing and connection handling settings |
| http | Defines the main HTTP server block and contains global HTTP configuration |
| server | Defines the configuration for an individual server block, including server-specific settings |
| location | Specifies configuration for a specific URL location within a server block |
| listen | Defines the IP address and port on which Nginx should listen for incoming connections |
| root | Specifies the document root directory for serving files |
| index | Defines the default file to serve when a directory is requested |
| proxy_pass | Sets the backend server to which requests should be forwarded when acting as a reverse proxy |
| rewrite | Allows rewriting or modifying the URL of a request based on defined rules |
| try_files | Specifies a series of files to attempt to serve in order, useful for fallback or error handling |
| access_log | Sets the file path for logging access messages |
| error_log | Sets the file path for logging error messages |
| gzip | Enables compression of HTTP responses to reduce the size of transmitted data |
| ssl_certificate | Specifies the path to the SSL/TLS certificate file for enabling HTTPS connections |
| ssl_certificate_key | Specifies the path to the SSL/TLS certificate’s private key file |
| include | Includes additional configuration files into the main Nginx configuration file |
| if | Allows conditional processing of configuration directives based on conditions |
| upstream | Defines a group of backend servers for load balancing or proxying |
| proxy_set_header | Sets an HTTP request header field value when acting as a reverse proxy |
| proxy_redirect | Sets the redirect configuration for reverse proxy responses |
| alias | Maps a location to a different directory path |
| error_page | Defines custom error pages for specific HTTP response codes |
| server_name | Specifies the server name(s) associated with a server block |
