OPS235 Lab 2 Braille

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OPS235 Lab 2 - Braille : Fedora 16 Installation on Virtual Machines

Introduction

A virtual machine is a software simulation of a computer which can be used as though it were actual hardware. It's possible to run multiple virtual machines on one computer, reducing hardware requirements and introducing flexibility. Some common uses of virtualization include:

  • Software testing -- Using multiple operating systems simultaneously on a single computer for testing and experimentation.
  • Network simulation -- Testing network services, protocols, and security scenarios with a small number of computers.
  • Isolation -- Protecting multiple sets of data by storing them on multiple virtual machines. If one of the virtual machines is compromised, the data on other virtual machines is still protected.
  • Server consolidation -- Reducing the number of physical servers in a network by moving physical machines to virtual machines. This saves hardware, administration, cooling, and electricity costs, and it can increase the utilization of hardware (by ensuring that the hardware is not under-loaded).
  • Load-balancing and disaster recovery -- It is possible to migrate virtual machines between different physical machines, to ensure that a workload is balanced across multiple computers, to allow routine hardware maintenance and upgrading, and to compensate for hardware failure or other disasters.

Objectives

  • Understand Virtualization
  • Use KVM virtualization on Fedora
  • Use Kickstart and Network Installation Methods

Prerequisites

  • Completion and Instructor "Sign-off" of Lab 1: OPS235 Lab 1

Linux Command Online Reference

See the manpages for:

  • virsh
  • gzip / gunzip

Resources on the Web

Performing Lab 2

Preparation

  1. Install the Fedora virtualization software: yum groupinstall "Virtualization" or pkcon install @virtualization The virtualization software installed is in three parts:
    • A system service named libvirtd that manages the VMs.
    • Tools to manage virtualization, including the virt-manager graphical tool and the virsh command-line tool.
    • The actual virtual machines themselves.
  2. Reboot your system.
  3. Start the virtualization service: systemctl start libvirtd

Investigation 1: Installing from a Live Disc

VM Details

Steps to Perform

  1. Record the current time.
  2. Run this command to start the installation of a virtual machine named fedora1: virt-install --connect qemu:///system --name fedora1 -r 768 --os-variant fedora16 --network network=default --disk /var/lib/libvirt/images/f16-ks-1,size=10 -l http://belmont.senecac.on.ca/fedora/releases/16/Fedora/x86_64/os/ -x ks=http://zenit.senecac.on.ca/~chris.tyler/fedora16-vda-ks.cfg --noautoconsole
  3. The virtual machine will stop when the installation is complete. You can see if the virtual machine is running with the command: virsh list
  4. Record the approximate time that the installation ends.
  5. Once the virtual machine has been installed, start it with this command: virsh start fedora1
  6. In order to connect to the virtual machine, you need to know:
    • The IP address.
    • The account name and password of a regular user.
    • The password for the root (administrator) user.
  7. To gather the information listed above, study the kickstart file. Record your answers.
  8. Using the information you gathered from the kickstart file, connect to the virtual machine: ssh accountname@IPaddress (substitute the correct account name and IP address)
  9. Enter the password when requested.
  10. On the virtual machine, determine:
    • The number of packages installed
    • The amount of free disk space
  11. Stop the virtual machine by typing, as the root user inside that virtual machine, the command: poweroff
  12. Confirm that the virtual machine is off by executing this command on your f16host: virsh list

Investigation 2

  1. Install another virtual machine by modifying the command used in Investigation 1. Incorporate these changes:
    1. Use the name "fedora2" for this virtual machine.
    2. Use a disk size of 15G
    3. Use the IP address 192.168.122.201
  2. Start fedora2 and confirm that you can connect to it.
  3. Shut down fedora2.

Investigation 3

  1. Make a copy of the kickstart file. Modify it so that the user account that is created has the same user ID as your matrix account. Place this file in a location where it can be accessed via a web browser (for example, in the public_html directory in your Matrix account).
  2. Modify the command used in Investigation 1 to incorporate these changes:
    1. Use the name "fedora3" for this virtual machine.
    2. Use the IP address 192.168.122.202
    3. Use your kickstart file instead of the original one.
  3. Start fedora3 and confirm that you can connect to it, using your Matrix ID and password.
  4. Shut down fedora3.

Investigation 2: Installing from the Network

Idea.png
Authenticate to the network
The rest of this lab uses network access. Be sure to authenticate to the network using your browser before proceeding.

Introduction

It is possible to install Fedora entirely from the network. In this investigation, you will install Fedora from a webserver on Seneca's LAN.

VM details

Steps

  1. Create the VM (called fedora2) as you did with the fedora1 virtual machine, except:
  2. Observe the boot process. How is it different from booting from an optical disc (CD/DVD)?
  3. Start the installation process (make certain to use information in the VM Details section above). When you get to the disk partitioning step, enable the checkbox labelled Review and modify partition layout.If an dialog box displays a permissions problem, then click yes to proceed. On the next screen, change the logical volumes as follows:
    • Reduce the size of the root LV to 8000 MB.
    • Add a logical volume with a size of 2000 MB and a mountpoint of /home (you can name it whatever you want, and use ext4 as the file-system type).
  4. On the software selection screen, select Graphical Desktop.
  5. On the same screen, select the "Fedora 16 - x86_64" and the "Fedora 16 - x86_64 - Updates". Leave "Installation Repo" selected. DO NOT enable the "Test Updates" repository.
  6. Complete the installation. Record the time taken to install, and compare this to the time taken by the previous installations.Record this information in the table contained in Investigation 4.

Answer the Investigation 2 observations / questions in your lab log book.

Investigation 3: Installing from the Network using Kickstart

Introduction

When Fedora is installed using the techniques you have used so far, the user is asked a number of questions. In some situations, it is better to provide the answers to these questions in a file rather than answer them individually. This type of file is called a kickstart file.

In this investigation, a kickstart file is provided for you. You can also create or modify a kickstart file using a regular text editor or a graphical tool.

VM details

Steps

  1. Create the VM as you did with the fedora2 virtual machine, specifying a network install as before, except:
  2. Observe the installation. How is it different from booting from an optical disc (CD/DVD)?
  3. Complete the installation. Record the time taken to install, and compare this to the time taken by the previous installations.
  4. What happens when the installation is finished?
  5. Take a look at the kickstart file (using the URL you entered) to determine the root password as well as the name and password for the first user account.
  6. Boot the virtual machine and log in (use the user ID and password information from the previous step). Compare the experience to the first time you booted the other virtual machines.Record this information in the table contained in Investigation 4.

Answer the Investigation 3 observations / questions in your lab log book.

Investigation 4: Updating and Comparing the VMs

  1. In each VM, run this command: yum update
  2. Record the answers to these questions in your log book:
    • How long did it take to run on each VM? How many packages were updated?
    • Why does it take longer in some VMs than others?

Complete the following table (and transfer into your lab2 log-book notes):

f16host fedora1 fedora2 fedora3
Installation Method Installation Disc Live Disc Network Installation Network Installation + Kickstart
Packages Installed
Updates Installed immediately after installation
Software could be selected during installation
Disk layout could be selected during installation
No questions asked during installation
Total installation time (after installation questions)
Amount of disk space used
Questions asked during first boot
Advantages of this type of installation
Disadvantages of this type of installation
This type of installation is recommended for...

Investigation 5: Managing Virtual Machines from the Command Line

Note.png
Manage virtual machines from the host
The commands used to manage virtual machines must be executed on the host (your disk pack) and not inside a virtual machine.
  1. Start the fedora1 virtual machine, and stop the fedora2 and fedora3 virtual machines.
  2. Enter these commands and note the result:
    • virsh list
    • virsh list --all
    • virsh list --inactive
  3. Start the fedora3 virtual machine from the command line: virsh start fedora3
  4. Repeat the commands from step 2 and notice any changes.
  5. Stop the fedora3 virtual machine: virsh shutdown fedora3


Note.png
Virtual Machine Does not Shutdown from Command
If the Virtual machine fails to shutdown from the virsh shutdown command, then you can go to the Virtual Machine manager and halt or shutdown within the VM itself, then you can click the PowerOff button in the VM window. You'll want to avoid a forced shutdown since those are equivalent to yanking the cord out of the wall on a physical machine!
  1. Confirm that fedora3 has been shut down.
  2. Execute this command: virsh dumpxml fedora3 >fedora3.xml
  3. Examine the file fedora3.xml. What does it contain? What format is it in?
  4. Make a copy of fedora3.xml called fedora3a.xml.
  5. Edit the file fedora3a.xml, making the following changes:
  • Change the name (in the file, not the file name) to fedora3a
  • Change at least one of the hexadecimal characters in the UUID. Do not change the length of the UUID. Valid hexadecimal characters are 0-9 and a-f.
  1. Issue this command: virsh define fedora3a.xml
  2. Issue the command virsh list --all and record any changes.
  3. Issue the command: virsh undefine fedora3a
  4. List all of the virtual machines again, and note any changes.

Answer the Investigation 5 observations / questions in your lab log book.

Investigation 6: How do I backup a virtual machine?

Important.png
Backing up VMs
Taking the time to backup the image of the Operating System's file system allows the user to return to a "restoration point" in case something bad occurs to the OS during a lab. Failure to take the time to make and confirm backups can result in loss of lab work for the student!
  1. Shut down all of the virtual machines.
  2. Change to the directory /var/lib/libvirt/images/. Note the size of the files in this directory. What do these files contain?
  3. Make a compressed backup of the fedora3.img file to your home directory with this command: gzip <fedora3.img >~YourUserId/fedora3.img.backup.gz
Stop (medium size).png
Make sure the backup is successful!
If there are any error messages, DO NOT proceed past this point. You're going to destroy your fedora3 virtual machine and restore it using the backup you have created -- if there are any problems with the backup, you will not have a working virtual machine, and will have to re-install it.
  1. Compare the size of the compressed and original files.
  2. Start the fedora3 VM.
  3. Make certain that you are in your fedora VM, and not in your Fedora main system.
  4. Wreck only your fedora 3 system! Try this command inside the fedora3 virtual machine (DO NOT do this on your main Fedora system, or you will have to repeat your lab2 and portions of your lab3!): rm -rf /*
  5. Shut down the VM.
  6. Restore the original image from the backup in your home directory (type this command carefully): gunzip <~YourUserId/fedora3.img.backup.gz >fedora3.img
  7. Restart the VM. Is it working normally?
  8. Create compressed backups of your other virtual machines.
  9. Answer this question in your log book:
  • In order to fully back up a virtual machine, what information should be saved in addition to the virtual machine image?
Important.png
Backing up VMs
It is essential to back up your VMs at the end of each lab, so you can easily restore them if something goes wrong in the next lab.
Idea.png
Shutting Down the Host while Virtual Machines are Running
If you shut down your host system while virtual machines are running, they will be suspended, and will resume the next time you boot your host system.

Answer the Investigation 6 observations / questions in your lab log book.

Investigation 7: Kickstart Files

Idea.png
SSHD and Firewall
If you have restarted your virtual machine fedora1, the sshd server you started in section 1-16 will no longer be running. In addition, the firewall will have reverted to its original state. In order to use scp, below, you will need to restart ssh and adjust the firewall again.

When you perform a non-Kickstart installation, the installation program creates a Kickstart file in the /root directory for reference.

  1. Obtain the kickstart files for all four of your installations (your disk pack f16host, plus the fedora1, fedora2, and fedora3 virtual machines). Copy them all to your f16host system (tip: use scp).
  2. Compare these files. What are the differences? Similarities? (Tip: you may want to use tools such as sdiff to help with the comparison).
  3. How could you use the kickstart file produced by the installation program to perform additional, identical installations?

Answer the Investigation 7 observations / questions in your lab log book.

Completing the Lab

Arrange evidence for each of these items on your screen, then ask your instructor to review them and sign off on the lab's completion:

  1. Three working virtual machines created.
  2. Four kickstart files.
  3. All virtual machines fully updated.
  4. All virtual machines backed up.
  5. Installation comparison table filled in.
  6. Lag Logbook (lab2) notes filled-in.

Preparing for the Quizzes

  1. What is the name of the Fedora installation program?
  2. Which factors recorded in your table (above) were due to the type of installation performed, and which factors were due to the amount of software installed?
  3. Which type of installation works best for confirming compatibility with hardware before installation? Why?
  4. Which type of installation works best for installing large numbers of computers? Why?
  5. What factors affect installation time?
  6. How can you reduce the number of software updates required immediately after installation?
  7. Why would you enable additional repositories during installation?
  8. What does the file /root/anaconda-ks.cfg contain, and how is it created?
  9. How do you start and stop virtual machines?
  10. How do you SSH into your virtual machines?
  11. What is the purpose of and relationship between these pieces of software?
    • libvirt
    • libvirtd
    • virsh
    • virt-manager
    • virt-install
    • kvm
  12. The kickstart installation (fedora3) was a network installation. Can a kickstart file be used with a DVD installation?
  13. The kickstart installation (fedora3) was fairly fast. Why? Under what circumstances would it take a long time, even on a fast network?
  14. What other types of installation sources are possible (besides Live Disc, Installation Disc, and Network?)
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