Apache is a web server. It is a free and open source web server software, released under the terms of Apache License 2.0. Apache is developed and maintained by an open community of the Apache Software Foundation.

 

For Web Hosting:

        In LINUX:

                       APACHE

                       GLASSFISH

                       NGNIX

                       Lighthttd

        In WINDOWS:

                       IIS

 

Following Webservers used:

        TOMCAT

        GLASSFISH

        JBOSS

        WEBSPHERE [IBM] à [MIDDLEWARE]

        WEBLOGIC

 

Root Path of APACHE

        /etc/httpd/

 

Configuration File

               /etc/httpd/conf/httpd.conf

 

Configuration file consist of 3 main sections

               1) GLOBAL Section                               (2nd Priority)

               2) MAIN Section                                     (3rd Priority)

               3) VIRTUAL HOST (VH) Section      (1st Priority)

APACHE IS A MODULAR SERVER

Apache is having built in 2 types of modules.

-        Static Module

-        Dynamic Module [DSO (Dynamic Shared Objects)]

 

# httpd -M ---------| Used to see the module details.

# httpd -l

Shared module means DSO

 

When these modules are loaded?

-        Whenever APACHE is running, STATIC modules always in RAM.

-        Dynamic modules (DSO) are loaded whenever it is required.

 

Where to see modules in the system?

-        # ls /etc/httpd/modules

 

How modules load in Apache?

-        Go to configuration file, In main section check “LoadModule” tag.

All the basic essential directives are managed by CORE Module.