Book Image

Mastering NGINX - Second Edition

By : Aivaliotis
Book Image

Mastering NGINX - Second Edition

By: Aivaliotis

Overview of this book

NGINX is a high-performance HTTP server and mail proxy designed to use very few system resources. But despite its power it is often a challenge to properly configure NGINX to meet your expectations. Mastering Nginx is the solution – an insider’s guide that will clarify the murky waters of NGINX’s configuration. Tune NGINX for various situations, improve your NGINX experience with some of the more obscure configuration directives, and discover how to design and personalize a configuration to match your needs. To begin with, quickly brush up on installing and setting up the NGINX server on the OS and its integration with third-party modules. From here, move on to explain NGINX's mail proxy module and its authentication, and reverse proxy to solve scaling issues. Then see how to integrate NGINX with your applications to perform tasks. The latter part of the book focuses on working through techniques to solve common web issues and the know-hows using NGINX modules. Finally, we will also explore different configurations that will help you troubleshoot NGINX server and assist with performance tuning.
Table of Contents (15 chapters)
10
A. Directive Reference
13
D. Persisting Solaris Network Tunings
14
Index

Predefined variables


NGINX makes constructing configurations based on the values of variables easy. Not only can you instantiate your own variables by using the set or map directives, but there are also predefined variables used within NGINX. They are optimized for quick evaluation and the values are cached for the lifetime of a request. You can use any of them as a key in an if statement, or pass them on to a proxy. A number of them may prove useful if you define your own log file format. If you try to redefine any of them, though, you will get an error message, as follows:

<timestamp> [emerg] <master pid>#0: the duplicate "<variable_name>" variable in <path-to-configuration-file>:<line-number>

They are also not made for macro expansion in the configuration—they are mostly used at runtime.

The following table lists the variables and their values defined in the http module:

HTTP variable names

Value

$arg_name

This variable specifies the name argument present...