Apache is structured mainly through its configuration files. You can add directives to the httpd.conf file to control Apache’s behavior.

There are two types of Apache directives: single line entries and block directives.

ServerName your_company.com

Block directives are enclosed in angle brackets ("< >") and always have a beginning and ending directive. The ending directive has a forward slash ("/").

Server Operation Directives
Apache can utilize a large number of directives. When you add modules, the modules produce even more directives.

The LoadModule Directive
The LoadModule directive instructs the Apache Web server software to load shared object libraries at startup. This should be the first directive in the configuration file so the module is available before the Web server uses it. The following is an example:

LoadModule foo_module modules/mod_foo.so

Refer to "Modules" on for more information on Apache modules.

The HostnameLookups Directive
The Apache Web server is configured by default to keep a log of the clients that access resources on your Web site. The log includes the hostname (i.e. some.remote.host) or just the IP address (i.e. 32.64.128.16). The value is set to "off" by default to improve your server performance. Additional latency is introduced into the server response process when the Web server is required to perform a hostname lookup that translates IP addresses into domain names.

Sites with even moderate loads should leave this directive off because hostname lookups can take considerable amounts of time.

The following is an example:

For more information, go to:

The ServerAdmin Directive
The ServerAdmin directive defines the e-mail address the server includes in error messages that it returns to the client.

The following is an example:

For more information, go to:

The ServerRoot Directive
The ServerRoot directive defines the directory in which the server resides. The default directory is /usr/local/apache, since this directory contains the subdirectories conf and logs. Relative paths for other configuration files are defined with respect to the ServerRoot directory.

The following is an example:

For more information, go to:

The ErrorLog Directive
When your Web server encounters an error, it will use the definition specified in the ErrorLog directive to handle the error. Typically, a filename is specified to which your Web server appends the error information. If the filename definition does not begin with a slash ("/"), then it is assumed to be relative to the ServerRoot. If the filename begins with a pipe ("|"), then it is assumed to be a command that is to be spawned by the Web server to handle the error information.

The following is an example:

For more information, go to:

The LogFormat Directive
The LogFormat directive sets the format of the default log file named by the TransferLog directive. You can also use this directive to define custom log file format types. Each log format type is defined by a format declaration enclosed in quotations followed by an optional identifier or a nickname. Examples of some LogFormat directives are included below. For more information about using log formats effectively, see "Web Logs"

The format declaration member of each LogFormat directive can contain literal characters copied into the log files, and “%” directives that are replaced in the log file. A sample of some of the “%” directives are shown below. (A complete list can be found on the Apache Web site.)

Examples:

For more information, go to:

Changing LogFormat
You can change the Web server log file format to the common log format (separate log files for the access, agent, and referrer data) by modifying your Web server configuration file /www/conf/httpd.conf like this:

You can also define your own log format by modifying the LogFormat directive above. After making the changes above, be sure to restart your VPS v2 Virtual Server Web server.

The TransferLog Directive

The TransferLog directive identifies the location of a file that will contain a record of all requests made to your Web server.

If you are using the CustomLog directive to define the format of your log files, the format of your TransferLog file will be defined by the most recent LogFormat directive (or Combined Log Format if no other default format has been specified). If you would like entries in your transfer log to be formatted with the Common Log Format, you will need to create a custom LogFormat definition.

You can also process your Transfer Log entries with an external application by defining your TransferLog using a file pipe ("|").The following is an example:

Or:

For more information, go to:

The ReferrerLog Directive

The ReferrerLog directive is used to identify the location of a file that will contain a record of all referrer information (i.e. information about Web sites that link to and "referred" users to your Web site). By default, your server is configured in the combined log format. As such, the referrer information is included in the access_log. If you want a separate log for referrer information, see "Changing LogFormat"

The following is an example:

For more information, go to:

The AgentLog Directive
The AgentLog directive is used to identify the location of a file that contains a record of all browser agent information. By default, your server is configured in the combined log format. As such, the agent information is included in the access_log. If you want a separate log for agent information, see "Changing the LogFormat"

The following is an example:

For more information, go to:

The ServerName DirectiveThe ServerName directive sets the hostname of the Web server.

The following is a usage example:

For more information, go to:

The KeepAlive Directive
The KeepAlive extension to HTTP, as defined by the HTTP/1.1 draft, allows persistent connections. These long-lived HTTP sessions allow multiple requests to be sent over the same TCP connection and in some cases have been shown to result in an almost 50% speedup in latency times for HTML documents with multiple images. The KeepAlive directive enables or disables KeepAlive support. Set the value of this directive to "on" in order to enable persistent connections. Set the value of the directive to "off" to disable KeepAlive support. The maximum number of requests that you would like the Web server to support per connection is defined with the MaxKeepAliveRequests directive.

The following is an example:

For more information, go to:

The MaxKeepAliveRequests Directive
The MaxKeepAliveRequests directive limits the number of requests allowed per connection when KeepAlive is on. If it is set to 0, unlimited requests will be allowed. It is recommended that this setting be kept to a high value for maximum server performance.

The following is an example:

For more information, see:

The KeepAliveTimeout Directive
The KeepAliveTimeout directive defines the number of seconds the Web server waits for a subsequent request before closing the connection to the remote host.

The following is an example:

For more information, go to:

The MaxRequestsPerChild Directive
The MaxRequestsPerChild directive sets the limit on the number of requests that an individual child server process will handle. After the MaxRequestsPerChild requests has reached its limit, the child process will die. If MaxRequestsPerChild is 0, then the process will never expire.

Setting MaxRequestsPerChild to a non-zero limit has two beneficial effects. First, it limits the amount of memory that process can consume by (accidental) memory leakage. Second, by giving processes a finite lifetime, it helps reduce the number of processes when the server load reduces.

The following is an example:

For more information, go to:

The VirtualHost Directive
The VirtualHost directive allows you to configure your Web server to subhost multiple domain names.

The following is an example:

For more information, go to:

Our Technical Support Pages

The DocumentRoot Directive
The DocumentRoot is the location from which Web pages are served, such as:

For more information, go to:

The DirectoryIndex Directive
When a URL request is received that does not explicitly identify a resource by name, (e.g. http://www.your_company.com), your Web server will attempt to retrieve the files defined by the DirectoryIndex directive. Several files may be defined. The Web server will return the first one that it finds.

The following is an example:

A request for http://www.your_company.com would return http://www.your_company.com/index.php if it existed, then http://www.your_company.com/index.htm if it existed, and so on until a match is found. If no match is found, then an index of the files contained in the directory is returned.

For more information, go to:

The FancyIndexing, IndexOptions, AddIcon, and IndexIgnore Directives
As noted above, the DirectoryIndex directive identifies specific files that should be searched for when a URL request is received that does not explicitly identify a resource. If the DirectoryIndex search fails and the Indexes option is set for the requested directory (see the httpd.conf <Directory> directive), then an index of files is generated and served the client agent. There are several directives that define the display of such an index of files.

For more information, go to:

The AccessFileName Directive
When returning a document to a client, the server looks for access control files in the requested resource directory as well as its parent directories. The AccessFileName directive sets the name of the file your Web server will look for to find access control definitions. For more information about access control files.

The following is an example:

For more information, see:

The DefaultType Directive
The DefaultType directive defines a MIME type for resources on your Web server that do not match file extensions found in your MIME types configuration file.

The following is an example:

For more information, go to:

The AddLanguage Directive
The AddLanguage directive is used to identify resources written in a specific language with a file extension. The AddLanguage directive is essential for content negotiation, where the server returns one of several documents based on the language preference of the client browser. For more information about content negotiation.

The following is an example:

For more information, go to:

The LanguagePriority Directive
The LanguagePriority directive allows you to give precedence to some languages in case of a "tie" during content negotiation, or if the browser client does not specify a language priority (which may happen with older browsers). Simply list the languages in decreasing order of preference. For more information about content negotiation.

The following is an example:

For more information, go to:

The Redirect Directive
The Redirect directive is used to redirect absolute URL pathnames to absolute URL addresses. This is especially useful if you have resources that have moved from one location to another and want to "redirect" requests for the document at the old location to the new location.

The following is an example:

For more information, go to:

The Alias Directive
The Alias directive allows documents to be stored in the local file system other than under the directory defined with the DocumentRoot directive.

The following is an example:

For more information, see:

The ScriptAlias Directive
The ScriptAlias directive has the same behavior as the Alias directive, except that in addition to defining an alias definition, the directive also marks the target directory as containing CGI scripts.

The following is an example:

For more information, go to:

The AddType Directive
The AddType directive allows you to add a new MIME type definition without editing the file defined by the TypesConfig directive. Your mime.types configuration file is fairly complete, so you will rarely need the AddType directive.

The following is an example:

For more information, go to:

The AddHandler Directive
The AddHandler directive maps a filename extension to a special handler.

Example:

Or:

For more information, go to:

The ErrorDocument Directive
The ErrorDocument directive defines the location of documents that should be displayed (or scripts that should be invoked) when the server encounters an error. The directive can map the error codes to documents or scripts on your local server or on a remote server.

When the error code is encountered, the Web server tells the browser client to redirect its request to the URL you defined with the error code. If no ErrorDocument definition exists for a specific error code, then the Web server outputs a hard coded error message that it has defined internally. Common error codes include 401, 403, 404, 406, and 500. Those error codes and their definitions are found in the following table:

Error Code	Definition
Error Code 401 – Authorization Failed	The requested resource required authentication, and the client failed to provide a valid login/password pair.
Error Code 403 – Permission Denied	The client has requested a resource that is forbidden.
Error Code 404 – Resource Not Found	The requested resource does not exist on the Web server.
Error Code 406 – Resource Not Acceptable	The requested resource was found on the Web server, but it could not be delivered because the type of the resource is incompatible with accepted types indicated by the client.
Error Code 500 – Internal Error	The requested resource does not exist on the Web server.
Error Code 501 – File Not Found	The requested file does not exist of the Web server.

See "Creating Custom Error Document Pages" for more information about custom error handling.

The following is an example:

For more information, go to:

Access Control Directives
Apache provides control directives that define a limited scope for the area of effect of a specific directive. Using these directives, you can define security, control access to sensitive materials, and identify how certain files should be treated.

The Directory Directive
The Directory directive defines access control and security settings for the directories that are accessible by your Web server. Each Directory directive is comprised of several sub directives. Some of these sub directives include Options, AllowOveride, and <Limit>. Many of the sub directives that can be included in the <Directory> definitions can be included in local access control files (see AccessFileName directive). In most cases, the default <Directory> definitions included in your httpd.conf file will be adequate for your needs (the default definitions are included below).

If you need to modify these definitions, consult the URL references listed below for a thorough presentation of the <Directory> directive and its sub directives.

The following is an example:

For more information, go to:

The MIME Types File (mime.types)
The MIME types configuration file determines how your VPS v2 Virtual Server's Web server maps filename extensions to MIME types that are returned to the browser. Your browser then maps these MIME types to "helper" applications or in-line plug-ins. Although the default mime.types configuration file includes a definition of the most common known MIME types, you are free to modify the file to add support for any additional MIME type that you desire.

Adding a New MIME Type Definition
Append the definition to the existing MIME types in the file in the following format (where type/subtype is the MIME type of the document whose filename ends with one of the extensions listed):

type/subtype extension1 extension2 … extensionN

The extension list includes any number of space-separated filename extensions. Examples of MIME type entries can be found in the default MIME types file included with your virtual Web service.