OPS335 Web Server Lab

Basic Apache (Web Server) Setup

This lab will show you how to set up the Apache Web server using a Fedora 17 installed PC.

Prerequisites

Your hard drive should have Fedora 17, 64 bit Live edition already installed.
You have Fedora 17, 64bit version on VM01, VM02, and VM03 Both your host and all VMs should have SELinux enabled.
Both host and all VMs should have all software updated.

Ensure the clocks on both machines are set to the correct date and time.

Testing your network

Start Firefox on your host and authenticate yourself on Sene2net with your LEARN account.
Ensure you can access the web on your host machine and all your VMs.

Install and test Apache on your VM01 and VM03

Login to vm01 and install the following packages:

 yum install httpd httpd-tools

Still on vm01 you can now start your web server with this command and enable the service to start at boot.

systemctl start httpd.service
systemctl enable httpd.service

Using a text browser such as lynx on vm01 go to localhost. You should get the "Fedora Test Page" which indicates your web server is running on the local virtual machine.
backup your existing iptables rules on vm01 and ensure it meets the following conditions:
- Allow all packets "to" and "from" the loop back interface "lo".
- Allow NEW connections to your ssh server and httpd.
- Allow all RELATED and ESTABLISHED connections.
- The default policy on the INPUT chain is set to DROP.
Using Firefox on the host go to address for vm01 "192.168.X.2" (your ip addressing may differ). You should get the "Fedora Test Page" which indicates you can access your web server on VM01 via network connection. Do not continue until this step works.
- Once you have this working, save your iptables.
You should also be able to open the webpage using the hostname of vm01.
Now create your own test page named index.html and put it into directory /var/www/html/. This does not have to anything fancy, just a basic html page with enough content for you to recognize it as your own. Reload the web page on the host - you should see your own test page now.
Repeat the above steps for vm03.
Now, as root on f17 (the gateway/host), try to forward incoming http connections to your host to the web server on vm01. Use an iptables command something like this

iptables -t nat -A PREROUTING -i *yourinterface* -p tcp --dport 80 -j DNAT --to 192.168.X.2

You will also need to create a rule in the FORWARD chain in the default table to accept connections to port 80.
To test this setup you'll need to ask a classmate on another PC to try to use Firefox to view your web page. S/he'll have to enter your host's external interface IP number (142.204.141.yyy) in Firefox's address window.
Login to your vm01 (and then vm03) as root, edit the Apache configuration file and change the port your webserver is listening for incoming connections from 80 to 8080.

vi /etc/httpd/conf/httpd.conf

Change your firewall rules on vm01 (and also vm03) to allow connections to this port (8080), and remove the previous rule to allow connections to port 80.
Restart the apache server on vm01 and vm03 (this may take a minute).
Go back to f17 and redo your iptables command to forward connections to port 80 (on your host) to the new port 8080 on vm01, removing the previous rule for port 80.
Verify that other students on their PCs can still view your web page.

Load balancing using iptables

Iptables can be used for load balancing connections. On your host machine add a rule(s) to the PREROUTING chain that will alternate connections bound for port 80 on your host machine to vm01 and vm03 (remove the other rules you just created before doing this).

iptables -t nat -I PREROUTING -p tcp --dport 80 -m state --state NEW -m statistic --mode nth --every 2 --packet 1 -j DNAT --to-destination 192.168.X.4:8080
iptables -t nat -I PREROUTING -p tcp --dport 80 -m state --state NEW -m statistic --mode nth --every 2 --packet 0 -j DNAT --to-destination 192.168.X.2:8080

Again ask another student to test that load balancing is indeed working.

Add missing DNS resource records

Edit your forward look-up zone file and add the following resource records.
- A mail record that points to vm02.
- Alases as follows:
  - f17 - alias router
  - vm02 - alias mail
  - vm01 - alias www1
  - vm03 - alias www2
- Add text records that identify the roles on each of these machines and a text record for the domain "This is < your full name here>'s OPS335 Domain".
- Once these records have been added, be sure to increment your Serial number for the zone file. While not crucial for the lab as we do not yet have a slave DNS server, getting into the habit ensures when needed slaves will be informed of the changes.

Adding Webmail to your domain

In order for our domain to offer webmail services to its users you will need to install the following packages on vm02

yum install squirrelmail httpd dovecot

The SquirrelMail files are in /usr/share/squirrelmail, create the a symbolic link to share those files on the internet.

ln -s /usr/share/squirrelmail /var/www/html/mail

Change directories and run the configuration script for SquirrelMail

cd /usr/share/squirrelmail/config
./conf.pl

Use the menu to select #2 - Server Settings. Edit #1 Domain - choosing your domain name, and #3 Selecting SMTP. Ensure you have saved the data then return to the main menu. From the main menu select option D - Set pre-defined settings for specific IMAP servers, then enter 'dovecot'.
From the main menu select '1. Organization Preferences', then select option #1 'Organization Name' and change this to your domain name.
Edit The Postfix configuration file and find the below line and add "$mydomain" to ensure delivery of emails sent to the domain and not just the host name.

mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain

Edit the dovecot configuration file and uncomment the following line

protocols = imap pop3 lmtp

And add to the bottom of the file

mail_location = mbox:~/mail:INBOX=/var/mail/%u

You will need to change the permissions on the mail directories for the users from the default 660 to 600.

chmod 0600 /var/mail/*

you should now start and enable dovecot, httpd and restart postfix if it was already running.
test your connection to SquirrelMail by opening a browser and navigating to vm02/mail. You should see a log in page. Sign in using your login credentials on vm02.
- You may receive an error stating: 'Error connecting to IMAP server: localhost. 13 : Permission denied'. If you do, run the command 'setsebool -P httpd_can_network_connect=1'. This will set an SELinux boolean to allow httpd connections across the network.
You will need to open ports on your firewall to allow connections to the webserver, and port forwarding on the host.

Completing the Lab

Give the full path names of the Apache log files.
What directory is the default server root? Give the full path name.
What directory is the default document root? Give the full path name.
What is the default configuration file for the Apache web server on Fedora 16? Give the full path name.
What is the default maximum number of connections allowed on the server by default?
What user/group does Apache run under on Fedora 16?
What exact command did you use to allow requests to port 80 to be forwarded to 8080 on your VM?
What specific command (give full details) would you need to use on f16 to forward ssh connections to vm01?
What is the web site for Apache?
What is Apache's current version number? Note: this may be different from the version running on Fedora 16.

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