Itis 2110 Lab 8 Installing a Web Server Apache

Overview of Lab
The Apache Lab will involve the installation and customization of setting up a web server. The Web server will be Apache 2.2. The lab will deliberately deviate from some of the “norms” or standard directories and naming conventions to show that changes from usual practice and defaults are easily done.
Overall the steps will be:
Install Apache and test default installation
Create the directories needed for the Web files
Customize Apache for displaying the Web files. (Allow directory structure to be shown)
Install a simple set of supplied html files to be browsed
Following a specific directory structure
Change the default for case of no file name given (Disallow root directory to be shown but allow a subdirectory structure to be shown)
Ensure the server can be browsed from another machine (e.g. the CentOS VM)
The whole lab will be done on one lab PC using 2 VMs: one Debian and one CentOS. Apache will be installed on Debian VM, the Web Server will be browsed from the CentOS VM.
Side benefits from this lab include:
Learning how to install packages on a Debian System
Re-enforce the use of the VM environment
Re-enforce use of vi editor
Part 1: New Linux Techniques Create and execute a script file
Note: the instructions say to use vi as your editor. Substitute your version of vi (vim or vim-tiny) as needed.
A script file is basically a small, low level program. The commands in the script file are executed by the shell (bash in this lab). Scripts are handy to automate tasks. Some of the things that can be done by a script:
make decisions (using if statements)
loop
call other scripts to be executed
read and write files
execute system commands
Useful information:
Parameters passed to a script are denoted by $1, $2, $3, … where $1 is the 1st parameter, $2 is the 2nd, etc.
The number of parameters is $#
Conditionals are done by an if…elif…else…fi structure
The if and elif are followed by a command that evaluates to true or false
The elif and else are optional
elif can be repeated
Only one else may be used, if needed
The if is closed with the fi statement
To stop a script use exit n
n = 0 is a normal exit
n = 1 is an error exit
If a value needs to be checked the test command is used
Numbers use conditionals like –gt, -lt, and -eq (greater than, less than, equal)
Strings use = or != (equal and not equal)
There are other comparisons that can be done, check the internet
Variables are case sensitive, and are UPPER case by convention for environment variables
Script one
The first script will be a simple aid in changing your network configuration. It will stop the NIC, open the file interfaces to be edited, and then restart the NIC after you have saved the interfaces file.
Create a file named netconfig.sh using your version of vi. Note that .sh is a de facto extension used for script files. The file will reside in your home directory, but since it is working with network files an id with root authority will be need to execute it.
Change to your home directory:
cd ~
Start vi and enter the following text (note: the # lines are comments):
Save and exit vi. Make sure when you exit vi you have a file named netconfig.sh.
The first line tells the system which shell to run (bash in this case
The next two line are variables that are used for the fully qualified name of the interfaces and resolv.conf files
To use a variable in a script you put a $ in front of the name
The forth line stops the NIC card
The fifth line starts the vi editor to edit the interfaces file
The sixth line is commented out. It is to edit the resolv.conf file. To edit that file uncomment that line.
The next line restarts the NIC card
The last two lines add the IP address of two servers in the lab to the resolv.conf file
Use chmod to make the file netconfig.sh executable:
chmod 744 netcofig.sh
This will make the file readable, writeable and executable by your user id and only readable by those in the group and rest of the world. Note that although the file is now executable by your userid, it will fail the ifdown and ifup commands since only root can do those commands.
To run the script enter: ./netconfig.sh eth0
The script expects one parameter, the name of the NIC card, in this case eth0. Change eth0 if it is different on your system. That beginning period and slash is important. The ./ is the "command" (it really means to run the program from the current directory) to run the following script program netconfig.sh in the PWD and that program is not in your PATH. Remember the script you created has a command to start vi. The script will pause at the vi command until you close vi. When vi opens make the desired changes to the interfaces file. When done save and close. The script will then continue by starting the NIC card, and then appending the nameserver information string to the end of the resolv.conf file.
Confirm and document** that the script executed properly by checking the contents of the interfaces file and the resolv.conf file. You can make any changes you wish when editing the interfaces file. Hint: you might use this script when installing Apache (the next Step in this lab). Note that when the script is executed the first time the ifdown command may generate an error if the network has not been started yet.
You will probably want to keep this script (with minor modifications) to run in later labs when you need to edit your interfaces file.
Script two:
This script will copy one of two preconfigured interfaces templates to interfaces. The two templates are interfaces.static and interfaces.dhcp. The script will be called go.sh and will have one parameter which will be either "static" or "dhcp". When the script is run it will stop the NIC, copy the appropriate file to interfaces, then restart the NIC.
First make two copies of interfaces:
Change to the networks file: cd /etc/network
Create the templates:
cp interfaces interfaces.static
cp interfaces interfaces.dhcp
Edit both templates with the values you wish to have in them
Then create the following script named go:
To run the script:
Make the script executable:
Run the script:
./go static
./go dhcp
./go dog
Will print the error message
**Document the script working and not working (bad parameter)
Here is an alternate version (go2) that does not use an if clause and has a second parm for the NIC. This version checks for the correct number of parameters, but does not check their value. It assumes they have been typed in correctly. Create the script, make sure it is executable, and then test it. Try it with no parameters, with the correct parameters, then with statics spelled wrong, and then finally with the wrong NIC interface, e.g. eth9.
**Document the working and one of the tests with a bad parameter.
Summary:
Scripts can make repetitive tasks easier. Scripts by convention end in .sh, but that is for human use only. The permissions for the script must be eXecutable for the owner, group or world to run them. The scripts go and go2 have no extension and they work perfectly well.
Part 2: Apache Step 1: Install Apache
The latest version of Apache is version 2.2. This package is available as an option from your previous install of the Debian OS. You will use the CLI to install.
If needed, change the VM network configuration to use DHCP, then restart the VM (or just the NIC)! You could use the script file you created above to do this.
Install
Do a CLI based install of Apache: apt-get install apache2
Test to see if install was successful
Perform a quick check to see if the base Apache installation worked.
Open up the Ice Weasel browser:
Applications Internet Iceweasel Web Browser
Browse “yourself”: in the URL entry box enter: localhost, and hit enter. That request should be directed to the default installation for Apache and display a web page that says: It Works!
**Be sure to capture the successful web page message for your lab report.
Take a quick tour of the Web Server
Look around in the Web Server installation to see what directories and files were installed:
Default configuration files are located at /etc/apache2.
Default document root for apache2 is at /var/www.
** Document what you found (text)
Step2: Create directories and copy files
In this procedure you will begin to set up and customize the environment for your Web Server. This will consist of creating your directory structure and copying pre-existing html files into them. Later the Apache server will be customized to display these files.
The home directory for the server will be apachelab with one subdirectory ITIS2110. Apachelab will have two html files: home.html and wf1.html, and one image file: constitution.jpg. Directory ITIS2110 will have two files: test1.html and test2.html, and two images: Sunset.jpg and Winter.jpg.
Open a terminal with root authority:
Applications -> Accessories -> Root Terminal
Create the directories at the root level (/)
mkdir /apachelab
mkdir /apachelab/ITIS2110
Copy the files to these directories
The files are available in multiple places on the hades.lab network. It is your responsibility to get the files in the correct directories. The Hades server may or may not be directly accessible from the Debian VM, depending on what IP address your VM is using. You might be able to use the Iceweasel browser on the Debian VM to display the files (browse them) and then use the browser to copy them to the temporary directory. The “gottcha” on this step is the target directory is not accessible (wrong permissions) by the standard user id and the browser most likely will only run from a standard user id. Don’t forget to also copy the picture files.
Locations:
lab302-web.hades.lab (172.16.1.250)
** Show your directory structure and content
Step3: Configure Apache
Now it is time to reconfigure the default configuration of Apache to serve your files. The configuration file is called default and is in the /etc/apache2/sites-available directory.
Open the configuration file for editing.
Note: it will be easiest to use vi from a root terminal since you will be changing files that your user id will not have permission to change.
From a root terminal:
vi /etc/apache2/sites-available/default
Change the default document root
Look for the line “DocumentRoot /var/www/”. Change the directory name to the new server root base directory /apachelab/. The line should now read: “DocumentRoot /apachelab/”.
Allow root indexes (show directory structure):
Find the first Options FollowSymLinks
to:
Options Indexes FollowSymLinks
Note: there may be slight variations on the Options line, just ensure the Indexes word is added if need be.
Edit the second - change the /var/www/ to /apachelab/ITIS2110
- If there is RedirectMatch directive put a comment mark (#) in front of it
Restart the Apache server:
There are two methods:
service apache2 restart
-or-
/etc/init.d/apache2 restart
You will use Iceweasel again to browse the localhost. You should now be able to browse the new web pages. Ensure all the links work. Document your effort. Try browsing localhost with no file name. You should see the directory structure on the returned document. Try it also with localhost/ITIS2110 as the URL. You should see another directory structure for that directory.
**Again, document your effort.
Step4: Change access to forbidden for the root directory
In Step 4 you will make browsing the directory structure for the root “forbidden”.
Forbidden directory browser for document root “/”
Look for this line “Options Indexes FollowSymLinks” and delete “Indexes”
Allow directory browsing for sub directory “/apachelab/ITIS2110”
The previous command forbids directory listings for root and all it’s subdirectories. Now we want to allow listings for the subdirectory ITIS2110 and its subdirectories. Double-check that the Directory tag for the ITIS2110 has the Options Indexes somewhere in it. E.g.
Options Indexes FollowSymLinks Multiviews
There may be other values with the Options.
Restart the apache server
/etc/init.d/apache2 restart
Applications -> Internet -> Iceweasel Web Browser
Use the URL localhost again to browse the Web server root directory. You should see a Forbidden 403 message pop up.
Try again with the URL localhost/ITIS2110, you should see the index of the directory
** Document your results for both the blocked and unblocked browses
Step 5: Ensure the Web Server is accessible by other clients
In this step you will ensure that the Web Browser works from another environment (e.g. workstation). To do this, the Debian VM will be used as the Web Server and another VM, e.g. CentOS, will be used as the client to do the browsing.
On Debian, use ifconfig or similar tools to find the IP address of the servers. Assume it is 192.168.1.123 in this case.
Start another VM with CentOS as the OS.
Start a browser in the CentOS VM (Ice Weasel or such).
Use the browser to open the Debian Web page
Enter the Debian IP address in the CentOS URL box
192.168.1.123 will be used as the example in this case
You should get the Forbidden message.
Change the URL to 192.168.1.123/home.html
You should see the home web page.
Use the links on the home page to ensure all four web pages can be navigated.
**Document your results.
Deliverables:
A well written lab report. The lab report should have an overview and a summary as well as documenting the work done and results (note the elements marked with a **), including the minimal following details:
Part 1
Documentation of ** items
Part 2
Listing of the Apache “default” file after install
Screen shot of the browser after visiting “localhost” (default install data)
Step 2
Listing of the affected directories and contents
Step3
Listing of the Apache “default” file after Step 3 changes
Screen shots of the web browser
After visiting “localhost”
After visiting “localhost/itis2110”
Step 4
Listing of the Apache “default” file after Step 4 changes
Screen shot of the web browser
After visiting “localhost” after forbidden directory browser for document root (shows Forbidden message)
After visiting “localhost/itis2110” (shows no forbidden message, just the directory)
Step 5
Screen shot for web browser from another VM (CentOS)
Visiting “debian_ vm_ ip”
Visiting “debian_ vm_ ip /itis2110”
Reminder: documenting text data with screenshots will result in point deductions
Last saved: 3/16/2015 9:18:00 AM
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