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Being one of the components of the LAMP architecture, it is important to ensure that the Apache Server is installed and running on the Linux distribution being used. The easiest and least intrusive way of checking this is by opening a web browser on the local system and attempting to view the localhost web location. If there is a positive response when opening localhost from the web browser, then the Apache HTTP server is installed and running on the system. If the response is a web error, then the Apache HTTP is not running properly or not installed on the system.

Downloading the Software

The Apache Software Foundation is responsible for maintaining and supporting the Apache HTTP Server.

Its website is http://www.apache.org which provides the details associated with the product lines that it offers and further information to install, configure and run the Apache HTTP Server on a wide range of operating systems. For the purpose of this course, the focus will be on installing and executing the Apache HTTP Server on the Linux distribution being used in the classroom environment.

Installing the Software

Once the files are downloaded to the operating system, it is time to extract the download file to an appropriate location for the server to execute from. In the linux environment, the choice used for the classrooms will be the /usr/local directory. This will be the location for all the software that will be installed in this class.

Configuring the Install Script

The next step is to configure the Apache HTTPd source tree for the Linux operating system and any additional specific requirements needed. The configuration of the install script is accomplished using the script configure included in the root directory of the distribution. There are multiple installation options that can be manipulated during the configuration. These configuration options are beyond the scope of this class. For class purposes, the default options will be chosen by running just the configure command without any options.

Build the Package

The next step is to build the various parts which form the Apache HTTPd package by simply running the make command. Due to the fact that the make command will build a base configuration it will take several minutes to compile. The actual time it takes to compile will vary widely depending on the hardware and the number of modules that have been enabled.

Once the package has been made with the make command, it is now time to install the package using make install. Once this step is accomplished, a directory called apache2 will be created that will house the apache server files.

Configuring

The Apache server is configured by placing directives (which pass optional settings into the Apache server) in plain text configuration files. By default, the main configuration file that the Apache server will look for is called httpd.conf. This file is located in the apache2/conf directory by default. The majority of configuration options associated with this file are beyond the scope of this class and the default httpd.conf directives will be used.

Static vs. Dynamic Modules

Apache can load static modules or they can be loaded dynamically. Dynamic is more common in the last few years.

It takes less time to load a dynamic module. In order to see what modules are installed apache has an info and a status module. We will enable those modules and use them to make sure we have all the tools that we need. Mod status and Mod info display the output as a web page so we will need to make sure that the modules are loaded and that we have configured apache to deliver a "virtual URL " to display the content.

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Starting and Testing the Server

To start the Apache server, choose the apache2/bin directory. This directory contains the files associated with executing the components of the Apache server. The Apache server can be started by executing apachectl start from this directory.

To test if the Apache server is working on the system, open a web browser on the local system and attempt to open http://localhost. If an error appears, the system is not configured properly and the steps should be repeated to determine the problem. If a web page appears, the server is running properly.

Lab 2-A

In this exercise you will determine if the Apache HTTP Server is currently running on the local operating system. If the Apache HTTP Server is not installed, you will follow the steps required to download and install the latest version.

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1. In your web browser, attempt to open the

localhost web page. If http://localhost displays a web page, then the Apache server is installed on your system and no additional steps in this lab are required. However, if an error is returned, complete the remaining steps to install the Apache server on your system.

2. In your web browser's toolbar text area, type:

httpd.apache.org/download.cgi This will open the download page for the Apache HTTPd Server.

3. In the best available version section, choose the tar & zipped Unix Source link

(httpd-#.#.#.tar.gz) and save the file to the /tmp directory.

The downloaded file will take some time to download and patience should be expected.

Note: The instructor may have already downloaded this file and made it available in a local file system, check with the instructor before downloading.

4. In the /usr/local directory, type the following:

tar -xvf /tmp/httpd-#.#.#.tar.gz replacing the #.#.# with the exact file identifier downloaded in step 3.

This will extract the file downloaded in step 3 into the /usr/local directory making a new subdirectory labeled httpd-#.#.#.

5. In the /usr/local/httpd-#.#.#

directory, execute the following command:

./configure --prefix=/usr/local/

apache2 --enable-mods-shared=

most

This step configures the Apache HTTPd source tree for your specific operating system with the root directory for the Apache server being the apache2 subdirectory in the /usr/local directory. In addition, the enable-mods-shared=most tells the apache install script to build most of the available loadable modules.

6. In the /usr/local/httpd-#.#.#

directory, execute the following command:

make

This step builds the various parts which form the Apache HTTPd install package.

7. In the /usr/local/httpd-#.#.# directory, execute

the following command: This step will actually install the Apache server install package. Once this step is accomplished, a directory

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8. With the apache server files completed, there are a few configuration options that must be entered into the httpd.conf file before we are completed with the Apache step of the LAMP installation. However, a best practice is to make copies of existing configuration files prior to changing them. In the /usr/local/apache2/conf directory, create a copy of the httpd.conf file by entering the following command:

cp ./httpd.conf httpd.conf.bak

The original httpd.conf is now copied to

httpd.conf.bak giving us the ability to go pack and start over if need be (without having to remember all the changes that we made to the file). In addition, adding components and then testing them before going on to adding the next component is not a bad approach if your configuration files continue to cause you problems.

9. With the original configuration copied it is time to edit the httpd.conf file using your favorite editor. For this example the vi editor will be used:

vi httpd.conf

vi stands for visual editor and is the default editor that comes with the Linux operating systems. This editor will allow us to make modifications to the httpd.conf file and complete the apache server setup.

Note: Refer to Appendix B for a simple list of vi commands if you are unfamiliar with this program.

10. First things that need to be addressed are the modules and their status (will they be loaded). The two modules that need to be loaded (among many) are mod_info and mod_status. You can search for the mod_info module by typing in vi the following:

/mod_info.so

You can locate the mod_status module in the httpd.config file by typing in vi the following:

/mod_status.so

If these lines are commented out (the start of the line contains a pound sign:#), please remove the comment. If you do not see this lines then add them. If you do not see mod_info.so or mod_status.so in your modules directory then contact your instructor

11. The next step is add the "Virtual URL's" for status and info to the httpd.conf file.

Locate the end of the file and add the following lines:

<Location /info>

SetHandler server-info

</Location>

<Location /status >

SetHandler server-status

</Location>

The first section is responsible for allowing mod_info's output to be available. mod_info provides a detailed configuration and module information for your server (corresponding to modules, mostly) in display-order that are hyper-linked.

The second section is responsible for allowing mod_status' output to be available. mod_status provides a representation of your web server's internal state and the comings and goings of its child processes.

12. Save your changes to the httpd.conf and exit the vi program.

The changes are saved to the file.

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13. Test the configuration file for typos by typing the following in the

/usr/local/apache2/bin directory:

./apachectl configtest

If the response is not "syntax OK" then return to the httpd.conf file and correct the error.

14. Once the configuration test of the httpd.conf file responds with "syntax OK", it is now time to start the server by executing the following command:

./apachectl start

This will start the Apache HTTPd server on your system.

Note: If an error is shown after executing this command that says "Could not reliably determine the server's fully qualified domain name ...", simply ignore this error for class purposes. This is stating that Apache does not know what server name to listen for.

15. Open the web browser on your system and attempt to browse to http://localhost/info and http://localhost/status which refers to the apache server running on your system.

If both of the web pages come up and provide

information about the server, then apache was configured correctly and is executing properly. If an error appears, ask your instructor for assistance.

16. Stop the Apache server after ensuring that it is properly configured and running by typing the following command:

./apachectl stop

This will stop the Apache HTTPd server on the system.

This step is important when installing the next two components of the LAMP architecture.