Oracle Technology Blog: Oracle HTTP Server

Showing posts with label Oracle HTTP Server. Show all posts

Friday, September 26, 2008

How to set OracleAS Portal homepage as OHS default homepage?

In the directory ORACLE_HOME/Apache/Apache/htdocs/, make a backup copy of the files

index.html.html and index.html.lang, where lang is the language code. For example, index.html.en is the index HTML file for English.

Edit index.html.lang by replacing the entire contents of the file with the following HTML redirection code:

<HTML>

<SCRIPT LANGUAGE=JavaScript> document.location="http://host.domain:port/pls/portal"

</SCRIPT>

Fine Tuning Oracle HTTP Server (OHS) in a production environment

The httpd.conf file, located in the directory ORACLE_HOME/Apache/Apache/conf, is a series of directives. Some directives may well require adjustment from their default settings in a production environment.

StartServers 5: Specifies that Apache will launch only five child processes onstartup. When there are more than five concurrent requests, Apache will have to spawn more processes dynamically.
MaxClients 150: States that Apache will permit only 150 concurrent connections. If more than this is attempted, users will receive Error 500 messages.
MaxrequestsPerChild 0: Setting it to, for example, 1,000 can do no harm and may help. The default of zero (which means an infinite number) may cause memory leak issues.
ExtendedStatus on: Controls the amount of information returned by the URL http://host.domain:port/server-status Off may be less of a security risk than on.
ServerAdmin you@your.address: Determines the e-mail address that will be displayed on some pages for users to mail the administrator. This default is not very helpful.

Thursday, September 25, 2008

Oracle AS Basics-Part V- How to configure Apache?

Apache is configured with the httpd.conf file. The file is read when Apache starts. This means that any changes will not be effected until the listener is restarted.

The httpd.conf file, located in the directory ORACLE_HOME/Apache/Apache/conf, is a series of directives, all in the form of token value pairs. Because Oracle Application Server stores configuration data in text files such as httpd.conf and in a centrally maintained repository, Oracle does not support manual editing of the configuration files. You should only adjust the Apache configuration by using the management tools provided with Oracle Application Server.

Oracle AS Basics- Part IV-Apache Processing Architecture

The Apache processing architecture is based on a parent process that runs all the time,and child processes that are launched on demand. On UNIX, the child processes are real processes; you can see them at the operating-system level by running the ps command. On Windows, the child processes are separate threads in a single multithreaded process.

Oracle AS Basics-Part III- Apache Modules

Apache modules are dynamically linked libraries that enhance Apache’s capabilities. They run as threads within Apache child processes; some modules carry out work themselves, others are control structures for external processes.

When Apache is enhanced with modules such as those supplied by Oracle, it becomes a routing process that receives URLs and dispatches them to the appropriate service, which

is implemented by the module.

There are a number of Apache modules developed by Oracle Corporation that are shipped with Oracle Application Server.

modplsql: This module accepts URLs that request the running of PL/SQL procedures within an Oracle database
modoc4j: This module accepts URLs that request the running of Java servlets. The Java is not run by modoc4j but by the OC4J instance, which is a process external to Apache.
modosso: This module enables the connection to the Single Sign-On (SSO) service
modossl: Apache can also be configured to use secure sockets using this module

Oracle AS Basics-Part II-Apache Web Listener - Oracle HTTP Server

The front end to an Oracle Application Server, the process to which users connect, is a web listener, the Oracle HTTP Server (OHS). This is in fact a distribution of Apache.All Oracle Application Server instances, whether infrastructure or middle tier, come with an Apache web listener. This web listener can optionally be front ended by a Web Cache. As a general rule, the Web Cache is used for middle tier instances but not for infrastructure instances.

Web listener is a process that monitors one or more ports on one or more addresses for incoming URLs from browsers. It parses these URLs into filenames, locates the files on disk, and copies them back to the browser. Oracle did not write its own web listener. Instead, it chose to distribute the Apache web listener.

The term web server is seriously confusing, as it combines the terms web listener and application server. For this reason, try to avoid using the term Apache web server. The

term HTTP server is more acceptable.

Web listener refer to the front-end processes that manage users’ web sessions.Application server refer to the back-end processes that run application software.

The Apache license does not permit distributors to modify Apache itself. But Apache does come with a mechanism whereby its behavior can be modified legally by creating Apache modules. An Apache module is a dynamically linked program that is invoked when appropriate URLs are received by the web listener. The web listener parses the URL and, rather than mapping it onto a file for download to the browser, will dynamically load and link the appropriate module and pass the request through to that module for further processing. The only difference between the Oracle distribution of Apache and other public domain distribution are the modules that Oracle has written.

Oracle Technology Blog