Apache HTTP Server Version 2.0
This document describes the files used to configure the Apache HTTP server.
Main Configuration Files
Apache is configured by placing directives in plain text configuration files. The main configuration file is usually called
httpd.conf. The location of this file is set at compile-time, but may be overridden with the
-fcommand line flag. In addition, other configuration files may be added using the
Includedirective. Any directive may be placed in any of these configuration files. Changes to the main configuration files are only recognized by Apache when it is started or restarted.
New with Apache 1.3.13 is a feature where if any configuration file is actually a directory, Apache will enter that directory and parse any files (and subdirectories) found there as configuration files. One possible use for this would be to add VirtualHosts by creating small configuration files for each host, and placing them in such a configuration directory. Thus, you can add or remove VirtualHosts without editing any files at all, simply adding or deleting them. This makes automating such processes much easier.
The server also reads a file containing mime document types; the filename is set by the
TypesConfigdirective, and is
Syntax of the Configuration Files
Apache configuration files contain one directive per line. The back-slash "\" may be used as the last character on a line to indicate that the directive continues onto the next line. There must be no other characters or white space between the back-slash and the end of the line.
Directives in the configuration files are case-insensitive, but arguments to directives are often case sensitive. Lines which begin with the hash character "#" are considered comments, and are ignored. Comments may not be included on a line after a configuration directive. Blank lines and white space occurring before a directive are ignored, so you may indent directives for clarity.
You can check your configuration files for syntax errors without starting the server by using
apachectl configtestor the
-tcommand line option.
Apache is a modular server. This implies that only the most basic functionality is included in the core server. Extended features are available through modules which can be loaded into Apache. By default, a base set of modules is included in the server at compile-time. If the server is compiled to use dynamically loaded modules, then modules can be compiled separately and added at any time using the
LoadModuledirective. Otherwise, Apache must be recompiled to add or remove modules. Configuration directives may be included conditional on a presence of a particular module by enclosing them in an
To see which modules are currently compiled into the server, you can use the
-lcommand line option.
Scope of Directives
Related Modules Related Directives
Directives placed in the main configuration files apply to the entire server. If you wish to change the configuration for only a part of the server, you can scope your directives by placing them in
<LocationMatch>sections. These sections limit the application of the directives which they enclose to particular filesystem locations or URLs. They can also be nested, allowing for very fine grained configuration.
Apache has the capability to serve many different websites simultaneously. This is called Virtual Hosting. Directives can also be scoped by placing them inside
<VirtualHost>sections, so that they will only apply to requests for a particular website.
Although most directives can be placed in any of these sections, some directives do not make sense in some contexts. For example, directives controlling process creation can only be placed in the main server context. To find which directives can be placed in which sections, check the Context of the directive. For further information, we provide details on How Directory, Location and Files sections work.
Related Modules Related Directives
Apache allows for decentralized management of configuration via special files placed inside the web tree. The special files are usually called
.htaccess, but any name can be specified in the
AccessFileNamedirective. Directives placed in
.htaccessfiles apply to the directory where you place the file, and all sub-directories. The
.htaccessfiles follow the same syntax as the main configuration files. Since
.htaccessfiles are read on every request, changes made in these files take immediate effect.
To find which directives can be placed in
.htaccessfiles, check the Context of the directive. The server administrator further controls what directives may be placed in
.htaccessfiles by configuring the
AllowOverridedirective in the main configuration files.
For more information on
.htaccessfiles, see Ken Coar's tutorial on Using .htaccess Files with Apache.