7 Create a Linux Server

The Linux operating system has been increasing in popularity for many reasons. Most Linux platforms are free and open-source with very active development communities. Linux is also very reliable in that it often does not require reboots when something goes wrong. Furthermore, Linux is very customizable so only the features that are required are installed. A bare-bones Linux distribution can run on as little as 58MB of RAM! Finally, most applications on Linux are free and open-source.

Many people are reluctant to use Linux because it generally uses a command line interface (CLI) instead of a graphical user interface (GUI) like Windows or Apple. However, all those easy-to-use images require a lot of RAM and CPU power, so using CLI allows the operating system to focus on the essentials. We use Linux in the GNS3 environment because it requires very little in the way of hardware resources. This allows us to build complex enterprise networks without overloading our hosting machine. This lab will help you download, install, and configure a Ubuntu Linux Server for use in a GNS3 environment.

Learning Objectives

• Successfully download, install, and run Ubuntu Server in a GNS3 environment
• Optional installs for later labs
  • • Phase II – DHCP Server – KIA
    • Phase III – DNS Server – BIND9
    • Phase IV – Text-Based Web Browser – w3m
    • Phase V – GUI – LXDE Desktop
    • Phase VI – Web Hosting Service – Apache2

Prerequisites

• Chapter 2 – Setting up a GNS3 environment
• Chapter 6 – Adding a VM to GNS3

Deliverables

• None – this is a preparatory lab that supports other labs in this book

Resources

• Download Ubuntu Server https://ubuntu.com/download/server

Contributors and Testers

• TBD

1. Download Ubuntu Server from https://ubuntu.com/download/server
2. Start Oracle Virtual Box Manager
3. Click on New
   

   

   1. Pick a name, for this example, we use something clever like “Ubuntu Server”
   2. Use the dropdown menu to select the Ubuntu Server ISO that you downloaded
   3. Click Skip Unattended Installation IMPORTANT!
   4. Click Next
   5. You can leave the hardware on its defaults –> click next
      

      

      NOTE: If you plan to install the GUI interface, you will need at least 50 GB of hard disk storage in the next step.

   6. Leave the default Virtual Hard Disk settings –> click next
      

      

   7. Review the summary and click on Finish
4. Start the Ubuntu Server VM
5. Use the arrow keys to Install Ubuntu Server
   

   

6. Use the arrow keys to select your language and your keyboard
   

   

7. Use the arrow keys to select Ubuntu Server and press done
   

   

8. Accept the default network connections and select Done
   

   

9. Enter a proxy address, if you need one (if you don’t know, then you don’t need one), then select Done
   

   

10. Enter an alternative Mirror if you know you need one; otherwise, just select Done
    

    

11. Use the default storage configurations and select Done for both screens
    

    

12. Confirm the action and select Continue
    

    

    1. For the profile information, the following is recommended
       

       

       Your Name: student
       Your Servers Name: ubuntu_server
       Pick a username: student
       Chose a password: Security1

13. There is no need to update to Ubuntu Pro, so skip it for now and continue
    

    

14. Select Install OpenSSH Server and continue
    

    

15. No snaps are needed – select done
    

    

16. Allow the installation and update to complete, then select Reboot Now
    

    

17. You might have to hit <enter> a couple of times, depending on the way your VirtualBox is configured
18. Log in using the credentials you created earlier

    NOTE: If you are new to Linux, please note that the password cursor does not move. This is a security feature that masks the number of characters in the password. Anyone who shoulder surfs can accelerate their password brute force efforts by knowing the length of the password.

1. At the terminal prompt, type

   sudo apt install kea

2. On the Kea password screen, select ‘configured_password’
   

   

3. For the password, use one of your own or use the book’s default Security1
4. Kea can be configured by typing

   sudo vi /etc/kea/kea-dhcp4.conf

5. The instructions to configure Kea are included in the file
6. You can also use this guide to configure Kea (https://www.techtutorials.tv/sections/linux/how-to-install-and-configure-kea-dhcp-server/)
7. Use Chapter 6 to add the Ubuntu Server to the GNS3 Working Environment

1. Install software and additional utilities

   sudo apt install -y bind9 dnsutils bind9-utils

2. The following commands will be used in later chapters:
   1. Modify the configuration file

      sudo nano /etc/bind/named.conf.options

   2. Configure master zone declarations

      sudo nano /etc/bind/named.conf.local

   3. Start DNS daemon

      sudo systemctl start named

   4. To restart

      sudo systemctl restart named

   5. To check status
      sudo systemctl status named

1.  Install by typing

   sudo apt install w3m

2. Run by typing

   w3m -v http://www.google.com

3. Exit the browser by pressing Ctrl-z

1. Update and upgrade the Linux server
   1. Update the Ubuntu Server

      sudo apt update

   2. Upgrade the Ubuntu Server

      sudo apt upgrade

2. Install the GUI

   sudo apt -y install lubuntu-desktop task-lxde-desktop task-lxqt-desktop

3. Select ‘lightdm’ as the default display manager
   

   

4. This can take a while
   

   

5. Reboot the server

   sudo reboot

6. Upon restart, select the lightweight GUI, Lubuntu
   1. Click on the little ball on the sign-in screen
      

      

   2. Select ‘Lubuntu’
      

      

   3. Press the back arrow to return to the login and enter the password you created
   4. The Lubuntu GUI is now working
      

      

1. Install a GUI on the Ubuntu Server by following the steps in Phase 6
2. Install Apache HTTP Server
   1. Install Apache by typing

      sudo apt install apache2

   2. Restart the Apache Server by typing

      sudo service apache2 restart

   3. Test that it is running by opening Firefox and typing 127.0.0.1 in the address bar
   4. Check that it says it works
      

      

3. Install MySQL database management system
   1. From a terminal, install MySQL by typing

      sudo apt install mysql-server

   2. Verify it was installed by viewing the version number by typing

      sudo mysql -v

   3. Quit the MySQL interface prompt by typing

      \q

   4. Set the password validation by typing

      sudo mysql_secure_installation

      1. Press y and set the password strength according to your needs
      2. Press y to remove anonymous users
      3. Press y to disallow remote root login
      4. Keep the test database by pressing n
      5. Reload the privilege tables by pressing y
   5. Test the operability of mysql
      1. Start mysql by typing

         sudo mysql -u root

      2. Create a database by typing

         create database <name>;

      3. List all the databases by typing

         show databases;

   6. You should have a screen that looks like
      

      

   7. To leave mysql and return back to the Ubuntu Server console, type

      exit

4. Install PHP web-server scripting language module
   1. From the terminal, install PHP by typing

      sudo apt install php

   2. View the version by typing

      php -v

   3. Make a check file by typing

      sudo vi /var/www/html/info.php

      1. Type i and add the following information

         <?php
         phpinfo();
         ?>

      2. Save the file by pressing the escape key followed by

         :wq

   4. Restart the Apache service by typing

      sudo service apache2 restart

   5. Test PHP by opening Firefox and typing the following into the web browser address bar 127.0.0.1/info.php
   6. You should get the following screen
      

      

End of Lab