Difference between revisions of "OPS235 Lab 3 - Fedora17"

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[[Category:OPS235]][[Category:OPS235 Labs]]
 
[[Category:OPS235]][[Category:OPS235 Labs]]
= Using Virtual Machines =
+
{{Admon/caution|THIS IS AN OLD VERSION OF THE LAB|'''This is an archived version. Do not use this in your OPS235 course.'''}}
 +
=Logical Volume Management and Software Package Management=
  
== Objectives ==
 
  
* Understand Virtualization
+
==Introduction==
* Use KVM virtualization on Fedora
 
* Use a variety of installation methods
 
** Live Image Installation
 
** Network Installation
 
** Kickstart Installation
 
  
== Reference Material ==
+
In this lab you're going to:
  
Virtualization
+
:* Learn how to add and remove software packages on your different Linux systems.
* [http://docs.fedoraproject.org/virtualization-guide/f12/en-US/html/ Fedora 12 Virtualization Guide]
+
:* Learn how to properly adjust your various Linux file systems by using and managing LVM both graphically (fedora2) as well as command line (fedora3).
  
Installation Methods
+
== Required Materials (Bring to All Labs) ==
* Live Image Installation
 
** [http://docs.fedoraproject.org/readme-live-image/en-US.html Fedora 12 Live Image Guide]
 
** [http://docs.fedoraproject.org/installation-quick-start-guide/f12/en-US/html/ Fedora 12 Installation Quick Start Guide]
 
* Network Installation
 
** [http://docs.fedoraproject.org/install-guide/f12/en-US/html/ Fedora 12 Installation Guide]
 
*** [http://docs.fedoraproject.org/install-guide/f12/en-US/html/s1-steps-network-installs-x86.html Preparing for a Network Installation]
 
*** [http://docs.fedoraproject.org/install-guide/f12/en-US/html/s1-begininstall-perform-nfs-x86.html Performing a Network Installation]
 
* Kickstart Installation
 
** [http://docs.fedoraproject.org/install-guide/f12/en-US/html/ Fedora 12 Installation Guide]
 
*** [http://docs.fedoraproject.org/install-guide/f12/en-US/html/sn-automating-installation.html Automating the Installation with Kickstart]
 
*** [http://docs.fedoraproject.org/install-guide/f12/en-US/html/ch-kickstart2.html Kickstart Installations]
 
*** [http://docs.fedoraproject.org/install-guide/f12/en-US/html/ch-redhat-config-kickstart.html Kickstart Configurator]
 
  
== Required Materials ==
+
* Fedora 17 LIVE CD
 +
* Fedora 17 x86_64 Installation DVD
 +
* SATA Hard Disk (in removable disk tray)
 +
* USB Memory Stick
 +
* Lab Logbook
  
* Removable disk pack with Fedora installed (see [[OPS235 Lab 2|Lab 2]]).
+
==Prerequisites==
  
== Introduction ==
+
* Completion and Instructor "Sign-off" of Lab 2: [[OPS235 Lab 2]]
  
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:
+
==Linux Command Online Reference==
 +
Each Link below displays online manpages for each command (via [http://linuxmanpages.com/ http://linuxmanpages.com]):
  
* Software testing -- Using multiple operating systems simultaneously on a single computer for testing and experimentation.
+
{|width="100%" cellpadding="5"
* Network simulation -- Testing network services, protocols, and security scenarios with a small number of computers.
+
|'''LVM Information Utilities:'''
* Isolation -- Protecting multiple sets of data by storing them on multiple virtual machines.
+
|'''LVM Management Utilities:'''
* 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).
+
|'''Additional Utilities:'''
* 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.
+
|- valign="top"
 +
|
 +
*[http://linuxmanpages.com/man8/vgs.8.php vgs]
 +
*[http://linuxmanpages.com/man8/lvs.8.php lvs]
 +
*[http://linuxmanpages.com/man8/pvs.8.php pvs]
 +
*[http://linuxmanpages.com/man8/vgdisplay.8.php vgdisplay]
 +
*[http://linuxmanpages.com/man8/lvdisplay.8.php lvdisplay]
 +
*[http://linuxmanpages.com/man8/pvdisplay.8.php pvdisplay]
 +
|
 +
*[http://www.centos.org/docs/5/html/Deployment_Guide-en-US/s1-system-config-lvm.html system-config-lvm] (Tutorial)
 +
*[http://linuxmanpages.com/man8/lvextend.8.php lvextend]
 +
*[http://linuxmanpages.com/man8/resize2fs.8.php resize2fs]
 +
*[http://linuxmanpages.com/man8/lvcreate.8.php lvcreate]
 +
*[http://linuxmanpages.com/man8/lvreduce.8.php lvreduce]
 +
*[http://linuxmanpages.com/man8/pvcreate.8.php pvcreate]
 +
*[http://linuxmanpages.com/man8/vgextend.8.php vgextend]
 +
|
 +
*[http://linuxmanpages.com/man8/mount.8.php mount]
 +
*[http://linuxmanpages.com/man8/umount.8.php umount]
 +
*[http://linuxmanpages.com/man8/yum.8.php yum]
 +
*[http://linuxmanpages.com/man8/rpm.8.php rpm]
 +
|}
  
In this lab, you will create three virtual machines. This also gives you an opportunity to experiment with different ways of installing Fedora. Later in this course you will install another operating system distribution in a virtual machines.
+
==Resources on the web==
 +
Additional links to tutorials and HOWTOs:
 +
'''Please read this page to get an overview of LVM:'''<br /><br />
 +
:* [[Logical Volume Management]] ('''Note:''' It is recommended to return to this guide as a reference when performing the next several investigations)
 +
:* [http://fedoranews.org/alex/tutorial/rpm/ Using the RPM Utility]
 +
:* [http://www.centos.org/docs/5/html/yum/ Using the YUM Utility]
  
You have already used a Fedora live disc and an installation disc. In both cases, the boot media (which you used to load the installation software) and the installation source (where the software that got installed came from) were the same: they CD/DVD provided both. However, the Fedora (and most other Linux distributions) permits you to use any combination of boot media and installation media:
+
= Software Package Management =
  
* Boot Media
+
== Investigation 1: How do you query the RPM database? ==
** CD or DVD
 
** Hard disk
 
** USB flash drive
 
** Network boot
 
  
* Installation source
+
RPM maintains a database of installed software. This information is very useful to system administrators. In Lab 3, you queried that database using RPM with the -q argument. When you query the RPM database, you can separately specify:
** CD or DVD
+
:* Which packages you want to do an <u>operational task</u> (like installing or removing a package), using a '''select-option'''
** Hard disk
+
:* What <u>information</u> you want about those packages, using a '''query-option'''
** USB flash drive
 
** Network HTTP or NFS software repository
 
  
When you installed Fedora in [[OPS235 Lab 2|Lab 2]], you did it interactively -- you manually specified all of the installation options, and then the installation process was started. This is fairly convenient for single-machine installations, but is time-consuming and possibly error-prone when repeated for dozens, hundreds, or thousands of machines.
+
'''Perform the following steps:'''
  
For large installations, it's possible to specify the installation options in a file so that no user intervention is required. This is called a ''kickstart'' installation.
+
# Using information from the man page for <code>rpm</code>, fill in this information:
  
== Instructions ==
+
{|width="100%" border="1" cellpadding="5"
 +
|-
 +
!Option
 +
!Meaning
 +
!Select or query option?
 +
!Example command
 +
|-
 +
| -a
 +
|Select all packages
 +
|select-option
 +
|
 +
|-
 +
| -l
 +
|
 +
|
 +
|
 +
|-
 +
| -i
 +
|Show the package information.
 +
|
 +
|
 +
|-
 +
| -f filename
 +
|
 +
|
 +
|
 +
|-
 +
|packagename
 +
|Select just this package
 +
|select-option
 +
|
 +
|}
  
=== Preparation ===
+
'''Answer the Investigation 1 observations / table contents in your lab log book.'''
  
{{Admon/tip|Update your Fedora Installation|It's a good idea to ensure that your Fedora installation is fully updated before proceeding. You can update your system with the graphical tool located on the menu at >System>Administration>Software Update (or type the command <code>gpk-update-view</code>), or by typing either of these commands: <code>pkcon update</code> or <code>yum update</code>}}
+
== Investigation 2: How do you install and remove software with RPM? ==
  
# Install the Fedora virtualization software: <code>yum groupinstall "Virtualization"</code> or <code>pkcon install @virtualization</code>  The virtualization software installed is in three parts:
+
# Use the graphical file manager (Nautilus) to change to the directory on your Installation DVD. Go to the sub-directory called '''Packages''' and then go to the sub-directory '''l''' (for files beginning with the letter l like the '''lynx''' package). You should see a file called: <code>lynx-2.8.7-8.fc17.x86_64.rpm</code>
## A system service named ''libvirtd'' that manages the VMs.
+
# Execute the following command: <code>rpm -i lynx-2.8.7-8.fc17.x86_64.rpm</code>
## Tools to manage virtualization, including the <code>virt-manager</code> graphical tool and the <code>virsh</code> command-line tool.
+
# Issue an RPM query to check that lynx is installed. Record this command in your lab log-book.
## The actual virtual machines themselves.
+
# Issue the following command: <code>rpm -e lynx</code>
# Start the virtualization service: <code>service libvirtd start</code>
+
# Issue an RPM query to verify that lynx is no longer installed. Record this command in your lab log-book.
# The firewall configuration is altered by the addition of the virtualization software. Restart the firewall so that these changes become active: <code>service iptables restart</code>
+
# Move to the appropriate sub-directory for packages that begin with the letter '''b'''.
# Start the graphical tool by selecting the menu option Applications>System Tools>Virtual Machine Manager or by typing the command <code>virt-manager</code>
+
# Issue the following command<code>rpm -i BackupPC-3.2.1-7.fc17.x86_64.rpm</code> and note the result
  
=== Investigation 1: Installing from a Live Disc ===
+
'''Answer the Investigation 2 observations / questions in your lab log book.'''
  
These are the details for the first virtual machine:
+
== Investigation 3: How do you install and remove software with ''yum''? ==
  
* Name: fedora1
+
{{Admon/note|Internet Connection|In order for yum to work you require a connection to the Internet. Establish this connection by using the browser to log into SeneNET}}
* Boot media: Fedora Live CD
 
* Installation source: Fedora Live CD
 
* Memory: 512MB
 
* Disk space: 10GB
 
* CPUs: 1
 
  
Perform these steps:
+
# Change to your home directory.
  
# In the Virtual Machine Manger, click on the icon to ''Create a Virtual Machine'' in the upper-left corner: <br />[[Image:Virt-manager1.png]]
+
<ol>
# A window will appear with the title ''New VM''. There are five steps to be completed; click Forward after each step:
+
<li value="2">Issue the command: <code>yum install BackupPC</code> and answer <code>y</code> to the question about installation.
# Step 1 of 5: Enter the virtual machine name and select ''Local install media''.<br />[[Image:Virt-manager2.png]]
+
  <ol type="a">
# Step 2 of 5: Insert the CDROM or DVD containing the Fedora Live Disc image. Wait a moment for the disc to be recognized, then select it as the install media. Set the ''OS type'' to Linux and the ''Version'' to Fedora 12.<br />[[Image:Virt-manager3.png]]
+
  <li>Where did ''yum'' get the BackupPC software?</li>
<!-- {{Admon/tip|Using an ISO image|Instead of using a physical CD or DVD, you can use an ISO image of a CD or DVD. The virtualization software will make this ISO image appear like an actual CD within the virtual machine. Because hard disks are faster then optical discs, this will work faster than an actual CD/DVD.}}{{Admon/note|Choosing the operating system type and version|The purpose of the ''OS type'' and ''Version'' fields is to fine-tune some of the virtual machine settings for best performance. The VM will work even if these are set incorrectly.}} -->
+
  <li>Why could ''yum'' install BackupPC when rpm couldn't?</li>
# Step 3 of 5: Set the memory to 512 MB and the number of CPUs to 1.<br />[[Image:Virt-manager4.png]]
+
  </ol>
# Step 4 of 5: This next step creates a disk file that will be used to simulate the virtual machine's disk drive. Select a size of 10 GB and checkmark the box labeled ''Allocate entire disk now''.<br />[[Image:Virt-manager5.png]]
+
</li>
# Step 5 of 5: Review the options that you have selected. '''Make a note of the storage location.''' If anything needs to be changed, use the ''Back'' button to go back and edit it; otherwise, click ''Finish''.<br />[[Image:Virt-manager6.png]]
+
<li>Issue an RPM query to verify that BackupPC is installed. Record this command in your lab log-book.</li>
# The virtual machine will now start. You will see a window which displays the virtual video card from the VM. The video It's important to note that the VM can (and often will) run even when this display is not present. The virtual machine is running from the live disc at this point, and no software has been installed on the ''hard drive'' of the virtual machine.
+
<li>Issue the command: <code>yum remove BackupPC</code></li>
# Login to the VM and double-click on the ''Install to Hard Drive'' icon. The installatin program, similar to the one used when installing Fedora in Lab 2, will appear. You will get a warning at one point during the installation process that the disk "may need to be re-initialized" -- this is simply a warning that the virtual disk is completely blank, and it is safe to select ''Re-initialize drive''.
+
<li>Issue an RPM query to verify that BackupPC is no longer installed. Record this command in your lab log-book.</li>
# During the installation process, when prompted for the hostname, enter "fedora1", when prompted for the timezone, select ''America/Toronto'', and when asked about storage, select ''Use Entire Disk''. '''Use the default values for all other fields.''' Notice that the installer does not ask you what software should be installed; compare the installation time to the amount of time it took to do your Lab 2 installation.
+
<li>Install <code>nled</code> using '''yum'''. Record this command in your lab log-book.</li>
# When the installation is complete, select the menu option System>Shutdown to stop the Live Disc.
+
<li>Issue this command: <code>yum info cups</code></li>
# Start the VM from its disk image by selecting Virtual Machine>Run from the virtual machine menu. You will get the ''Firstboot'' configuration questions during the boot process (asking you to create a user, set the date and time, and optionally send the hardware profile to the Fedora Project). Create a user with the same name as your Matrix account.
+
</ol>
# Login using the new user account.
+
::* Based on the result, do you think that cups is a useful package for your system? If not, try removing it.
# Enable SSH access to your virtual machine with these commands: <code>service sshd start; chkconfig sshd on</code>
+
<ol>
# Find out the IP address of your virtual machine: <code>ifconfig eth0</code>
+
<li value="8">Unused and unneeded software can present a security risk and ties up disk space needlessly. Find at least 4 other packages that you're not using on your system, and remove them. Be careful to ensure that removing those packages does not also remove other software that you do need.</li>
# Confirm that you can ssh to your virtual machine from the host (your main Fedora installation): <code>ssh ''IPaddress''</code>
+
</ol>
  
=== Investigation 2: Installing from the Network ===
+
'''Answer the Investigation 3 observations / questions in your lab log book.'''
  
{{Admon/tip|Authenticate to the network|The rest of this lab uses network access. Be sure to authenticate to the network using your browser before proceeding.}}
+
=Logical Volume Management (Introduction)=
  
VM details:
+
== Check Current LVM Information Prior to Performing Investigations ==
  
* Name: fedora2
+
'''LVM''' ('''Logical Volume Management''') is used to manage hard disk drives / partitions for Unix/Linux systems. LVM provides more flexibility than just working with hard disks / hard disk partitions. '''Volume Groups''' are areas used to define '''Physical Volumes''' (i.e. hard disks, disk partitions, or other forms of storage devices). '''Logical Volumes''' are then used to relate directories (mount points) to a specific physical volume or for a "range" or "span" of physical volumes.
* Boot media: Network installation
 
* Installation source: http://belmont.senecac.on.ca/fedora/releases/12/Fedora/x86_64/os/
 
* Memory: 512MB
 
* Disk space: 10GB
 
* CPUs: 1
 
  
Steps:
+
Therefore, LVM allows more flexibility and growth potential for Linux systems (for example, having Logical volumes span multiple hard disks). Fedora uses LVM by default upon installation. Other Linux distributions may provide the capacity to install LVM, or later install and then use Logical Volume Management.
# Create the VM as you did with the ''fedora1'' virtual machine, except:
 
#* In step 1 of 5, set the installation type to "Network Install (HTTP, FTP, or NFS)"
 
#* In step 2 of 5, provide the URL http://belmont.senecac.on.ca/fedora/releases/12/Fedora/x86_64/os/
 
#*
 
# Observe the boot process. How is it different from booting from an optical disc (CD/DVD)?
 
# Start the installation process. When you get to the disk partitioning step, enable the checkbox labelled ''Review and modify partition layout''. On the next screen, change the logical volumes as follows:
 
#* Reduce the size of the root LV to 4000 MB.
 
#* Add a logical volume with a size of 1000 MB and a mountpoint of /home (you can name it whatever you want).
 
# On the software selection screen, uncheck the box for ''Office and Productivity'' (as well as the other software choices).
 
# On the same screen, select the "Fedora 12 - x86_64" and the "Fedora 12 - x86_64 - Updates". ''DO NOT'' enable the "Test Updates" repository.
 
# Complete the installation. Record the time taken to install, and compare this to the time taken by the previous installations.
 
  
=== Investigation 3: Installing using Kickstart ===
+
'''Although the concept of LVM is simple, it takes practice and preparation (or "thinking ahead") in order to correctly use this valuable tool'''. It is important for students to gain an understanding of LVM, and how to manage their file-systems using LVM. It is recommended for students to read the following resource prior to this lab and/or return to the following resource while performing this lab: [[Logical Volume Management]]
 +
 +
At this point, having completed [[OPS235 Lab 2|Lab 2]] you should have roughly the following disk storage setup:<br />
 +
('''Note:''' These results are output from the '''vgs''', '''lvs''', and '''pvs''' commands that provide volume group, physical volume and logical volume information for each of the virtual machines that you created in lab2. Before proceeding, check these values with your own system to see if you are generally "on the right track".<br /><br />
  
{{Admon/tip|Authenticate to the network|The rest of this lab uses network access. Be sure to authenticate to the network using your browser before proceeding.}}
+
* '''fedora1'''
  
VM details:
+
  VG        #PV #LV #SN Attr  VSize VFree
 +
  vg_fedora1  1  2  0 wz--n- 9.50g    0
  
* Name: fedora2
+
  PV        VG        Fmt  Attr PSize PFree
* Boot media: Network installation
+
  /dev/vda3  vg_fedora1 lvm2 a-- 9.50g    0
* Installation source: http://belmont.senecac.on.ca/fedora/releases/12/Fedora/x86_64/os/
 
* Kickstart location: http://zenit.senecac.on.ca/~chris.tyler/fedora3-ks.cfg
 
* Memory: 512MB
 
* Disk space: 10GB
 
* CPUs: 1
 
  
Steps:
+
  LV      VG        Attr  LSize Origin Snap%  Move Log Copy%  Convert
# Create the VM as you did with the ''fedora2'' virtual machine, specifying a network install as before, except:
+
  lv_root vg_fedora1 -wi-ao 8.03g                                   
#* In step 2 of 5, after entering the URL for the installation source, click on the ''URL Options'' control.
+
  lv_swap vg_fedora1 -wi-ao 1.47g
#* Enter the Kickstart URL: http://zenit.senecac.on.ca/~chris.tyler/fedora3-ks.cfg
 
# Observe the installation. How is it different from booting from an optical disc (CD/DVD)?
 
# Complete the installation. Record the time taken to install, and compare this to the time taken by the previous installations.
 
# What happens when the installation is finished?
 
# Take a look at the kickstart file to determine the root password as well as the name and password for the first user account.
 
# Boot the virtual machine and log in. Compare the experience to booting the other virtual machines.
 
  
=== Investigation 4: Updating the VMs ===
+
* '''fedora2'''
  
# In each VM, run this command: <code>yum update</code>
+
  VG        #PV #LV #SN Attr  VSize  VFree
# How long does it take to run?
+
  vg_fedora2  1  3  0 wz--n- 14.50g 3.25g
# Why does it take longer in some VMs than others? Why are some VMs completely up-to-date?
 
  
=== Investigation 5: How do I backup a virtual machine? ===
+
  PV        VG        Fmt  Attr PSize  PFree
 +
  /dev/vda3  vg_fedora2 lvm2 a--  14.50g 3.25g
  
# Shut down all of the virtual machines.
+
  LV      VG        Attr  LSize Origin Snap%  Move Log Copy%  Convert
# Change to the directory <code>/var/lib/libvirt/images/</code>. Note the size of the files in this directory.
+
  lv_home vg_fedora2 -wi-ao 1.97g                                   
# Make a compressed backup of the <code>fedora3.img</code> file with this command: <code>gzip <fedora3.img >fedora3.img.backup.gz</code>
+
  lv_root vg_fedora2 -wi-ao 7.81g                                   
# Compare the size of the compressed and original files.
+
  lv_swap vg_fedora2 -wi-ao 1.47g
# Start the ''fedora3'' VM.
 
# Wreck it! Try this command: <code>rm -rf /</code>
 
# Shut down the VM.
 
# Restore the original image from backup: <code>gunzip <fedora3.img.backup.gz >fedora3.img</code>
 
# Restart the VM. Is it working normally?
 
# Create compressed backups of your other virtual machines.
 
  
== Preparing for the Quizzes ==
+
* '''fedora3  (Note:  This VM has no GUI installed)'''
 +
 +
  VG        #PV #LV #SN Attr  VSize VFree
 +
  vg_fedora3  1  3  0 wz--n- 9.51g    0
  
# What are the advantages and disadvantages of each type of installation?
+
  PV        VG        Fmt  Attr PSize PFree
# Which type of installation works best for confirming compatibility with hardware before installation? Why?
+
  /dev/vda3  vg_fedora3 lvm2 a--  9.51g    0
# Which type of installation works best for installing large numbers of computers? Why?
+
 
# What factors affect installation time?
+
  LV      VG        Attr  LSize  Origin Snap%  Move Log Copy%  Convert
 +
  lv_home vg_fedora3 -wi-ao  1.00g                                   
 +
  lv_root vg_fedora3 -wi-ao  8.00g                                   
 +
  lv_swap vg_fedora3 -wi-ao 520.00m                                   
 +
 +
* '''f17host (i.e. "removable hard disk" or "disk pack")'''
 +
 
 +
Does not use LVM. Confirm this using the same commands used above.
 +
 
 +
{{Admon/note|VM Backups and Recovery|Most of these investigations will take place in your virtual machines. If you make a significant mistake, your virtual machine may not boot. Remember that you created backups of your virtual machines in Lab 2, and you can restore them if something goes wrong.<br /><br />'''Remember: if you did not create backups for all of your VMs, then you don't have any restoration points to fall-back to!'''|}}
 +
 
 +
== Investigation 4: Extend the size of lv_root using command-line tools ==
 +
 
 +
Perform this investigation in fedora3.
 +
 
 +
Let's say that you have run out of disk space on your computer (fedora3), you need more space on the root filesystem, perhaps to host more webpages or a larger database or new software. What are your options? Getting a replacement harddrive would probably require reinstallation of the operating system and backup/restore of the data.
 +
 
 +
Because we're using LVM though - we can avoid that. We can add a new harddrive (which will serve as a physical volume) to the volume group, and extend the root logical volume to make use of the new available space.
 +
 
 +
'''Perform the following operations to increase the size of lv_root in fedora3:'''
 +
 
 +
<u>'''<font>Steps:</font>'''</u>
 +
 
 +
<ol>
 +
<li>Run the following commands and make note of the output:</li>
 +
  <code>ls /dev/vd*
 +
  pvs
 +
  vgs
 +
  lvs
 +
  df -h</code>
 +
<li>Open the fedora3 virtual machine console</li>
 +
<li>Go to the hardware details view</li>
 +
<li>Click "Add Hardware" and add a new storage device of 2GBs, make sure it's a VirtIO disk.</li>
 +
<li>Go back to the console view</li>
 +
<li>Run the same ls command now, what's changed?</li>
 +
<li>Now we'll make the new device as a physical volume, add it to the volume group, and extend lv_root:</li>
 +
  <code>pvcreate /dev/vdb
 +
 
 +
  vgextend vg_fedora3 /dev/vdb
 +
 
 +
  lvextend -l +100%FREE -r vg_fedora3/lv_root</code>
 +
<li>Now rerun the ls/pvs/vgs/lvs/df commands. What has changed and what caused those changes?</li>
 +
<li>Among the changes, note that your root filesystem is now 2GB bigger - and you have not even rebooted your machine!</li>
 +
</ol>
 +
 
 +
'''Answer the Investigation 4 observations / questions in your lab log book.'''
 +
 
 +
== Investigation 5: How are LVMs managed using system-config-lvm? ==
 +
 
 +
'''Perform this investigation on the VM named ''<u>fedora2</u>''.'''
 +
[[Image:Ops235_lab4_1.png|thumb|right|Screenshot of system-config-lvm in Fedora. Click to enlarge.]]
 +
# Let's learn to administer (manage) our LVM graphically for our '''Fedora2''' Virtual Machine.<br />Fedora provides a tool called <code>system-config-lvm</code> to graphically administer LVM. It will appear on the menu as '''Application'''>'''Other'''>'''Logical Volume Management'''. The package may not be installed by default, so you will need to install it by issuing: (<code>yum install system-config-lvm</code>).
 +
<ol>
 +
<li value="2">Use this tool to determine the current LVM configuration by clicking on the appropriate element and reading the properties in the right-hand panel -- write down the answers:
 +
<ol type="a">
 +
  <li>What are the names and sizes of the '''PV'''s?</li>
 +
  <li>What is the name and size of the '''VG'''?</li>
 +
  <li>What are the names and sizes of the '''LV'''s?</li>
 +
  <li>Is there any space in the VG which is not allocated to a LV?</li>
 +
</ol>
 +
</li>
 +
<li>Increase the size of the home file-system to '''2 GB''':
 +
  <ol type="a">
 +
  <li>Click on the LV containing the '''home''' filesystem.</li>
 +
  <li>Click on ''Edit Properties''.</li>
 +
  <li>Change the size to '''2 GB''' and click ''Ok''.</li>
 +
  </ol>
 +
<li>Create a '''new 2G LV''' (LV Properties: linear) containing an ext4 filesystem named lv_archive and mount it at '''/archive'''
 +
  <ol type="a">
 +
  <li>Click on ''Logical View''.</li>
 +
  <li>Click the ''Create New Logical Volume''.</li>
 +
  <li>Set the name, size, filesystem, and mount point.</li>
 +
  <li>Click ''Ok''.</li>
 +
  </ol>
 +
  <li>Backup <code>'''/etc'''</code> into <code>'''/archive'''</code></li>
 +
</ol>
 +
::* Copy the files in /etc into the filesystem mounted at <code>/archive</code><br />(use the graphical tools or the command line. If using cp, remember to use the -R option).
 +
<ol>
 +
<li value="6">Shrink the size of <code>lv_archive</code> to '''1 GB'''.</li>
 +
<li>Try shrinking the home file-system. What happens? Why?</li>
 +
</ol>
 +
 
 +
'''Answer the Investigation 5 observations / questions in your lab log book.'''
 +
 
 +
= Updated backup instructions =
 +
 
 +
If you completed this lab correctly - please make sure you are still making full backups of your virtual machines.
 +
 
 +
Remember adding a new harddrive to fedora3? You will need to back up that drive as well. If you don't - you will only have half of your machine backed up, which is of no use for a recovery.
 +
 
 +
= Completing the lab =
 +
 
 +
{{Admon/important|Time for a new backup!|If you have successfully completed this lab, make a new backup of your virtual machines.}}
 +
 
 +
'''Notes:'''
 +
# rpm command options
 +
# yum command options
 +
# How to use pvs/vgs/lvs/df/pvcreate/vgextend/lvextend
 +
# Answer to this question "What is the license of the nautilus package?"
 +
 
 +
'''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:'''
 +
# nled installed on the host (disk pack - main system f16host).
 +
# Unnecessary/unused packages have been deleted (list at least 4, and show that they are no longer installed).
 +
# Fresh backup of the virtual machines.
 +
 
 +
= Preparing for Quizzes =
 +
 
 +
# What is a VG? PV? LV?
 +
# What commands are used to determine VG / PV / LV information?
 +
# What does yum do that rpm does not?
 +
# List the steps to install a package via rpm command.
 +
# List the steps to determine detailed information regarding an install package.
 +
# List the steps to remove a package via rpm command.
 +
# List the steps to install a package using the yum command.
 +
# List the steps to remove a package using the yum command.
 +
# What is the total size of the "main" VG on your system?
 +
# How do you create a LV?
 +
# How do you delete an LV?
 +
# How would you increase the size of the root filesystem by 50 MB?

Latest revision as of 12:31, 24 September 2018

Stop (medium size).png
THIS IS AN OLD VERSION OF THE LAB
This is an archived version. Do not use this in your OPS235 course.

Logical Volume Management and Software Package Management

Introduction

In this lab you're going to:

  • Learn how to add and remove software packages on your different Linux systems.
  • Learn how to properly adjust your various Linux file systems by using and managing LVM both graphically (fedora2) as well as command line (fedora3).

Required Materials (Bring to All Labs)

  • Fedora 17 LIVE CD
  • Fedora 17 x86_64 Installation DVD
  • SATA Hard Disk (in removable disk tray)
  • USB Memory Stick
  • Lab Logbook

Prerequisites

  • Completion and Instructor "Sign-off" of Lab 2: OPS235 Lab 2

Linux Command Online Reference

Each Link below displays online manpages for each command (via http://linuxmanpages.com):

LVM Information Utilities: LVM Management Utilities: Additional Utilities:

Resources on the web

Additional links to tutorials and HOWTOs: Please read this page to get an overview of LVM:

Software Package Management

Investigation 1: How do you query the RPM database?

RPM maintains a database of installed software. This information is very useful to system administrators. In Lab 3, you queried that database using RPM with the -q argument. When you query the RPM database, you can separately specify:

  • Which packages you want to do an operational task (like installing or removing a package), using a select-option
  • What information you want about those packages, using a query-option

Perform the following steps:

  1. Using information from the man page for rpm, fill in this information:
Option Meaning Select or query option? Example command
-a Select all packages select-option
-l
-i Show the package information.
-f filename
packagename Select just this package select-option

Answer the Investigation 1 observations / table contents in your lab log book.

Investigation 2: How do you install and remove software with RPM?

  1. Use the graphical file manager (Nautilus) to change to the directory on your Installation DVD. Go to the sub-directory called Packages and then go to the sub-directory l (for files beginning with the letter l like the lynx package). You should see a file called: lynx-2.8.7-8.fc17.x86_64.rpm
  2. Execute the following command: rpm -i lynx-2.8.7-8.fc17.x86_64.rpm
  3. Issue an RPM query to check that lynx is installed. Record this command in your lab log-book.
  4. Issue the following command: rpm -e lynx
  5. Issue an RPM query to verify that lynx is no longer installed. Record this command in your lab log-book.
  6. Move to the appropriate sub-directory for packages that begin with the letter b.
  7. Issue the following command: rpm -i BackupPC-3.2.1-7.fc17.x86_64.rpm and note the result

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

Investigation 3: How do you install and remove software with yum?

Note.png
Internet Connection
In order for yum to work you require a connection to the Internet. Establish this connection by using the browser to log into SeneNET
  1. Change to your home directory.
  1. Issue the command: yum install BackupPC and answer y to the question about installation.
    1. Where did yum get the BackupPC software?
    2. Why could yum install BackupPC when rpm couldn't?
  2. Issue an RPM query to verify that BackupPC is installed. Record this command in your lab log-book.
  3. Issue the command: yum remove BackupPC
  4. Issue an RPM query to verify that BackupPC is no longer installed. Record this command in your lab log-book.
  5. Install nled using yum. Record this command in your lab log-book.
  6. Issue this command: yum info cups
  • Based on the result, do you think that cups is a useful package for your system? If not, try removing it.
  1. Unused and unneeded software can present a security risk and ties up disk space needlessly. Find at least 4 other packages that you're not using on your system, and remove them. Be careful to ensure that removing those packages does not also remove other software that you do need.

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

Logical Volume Management (Introduction)

Check Current LVM Information Prior to Performing Investigations

LVM (Logical Volume Management) is used to manage hard disk drives / partitions for Unix/Linux systems. LVM provides more flexibility than just working with hard disks / hard disk partitions. Volume Groups are areas used to define Physical Volumes (i.e. hard disks, disk partitions, or other forms of storage devices). Logical Volumes are then used to relate directories (mount points) to a specific physical volume or for a "range" or "span" of physical volumes.

Therefore, LVM allows more flexibility and growth potential for Linux systems (for example, having Logical volumes span multiple hard disks). Fedora uses LVM by default upon installation. Other Linux distributions may provide the capacity to install LVM, or later install and then use Logical Volume Management.

Although the concept of LVM is simple, it takes practice and preparation (or "thinking ahead") in order to correctly use this valuable tool. It is important for students to gain an understanding of LVM, and how to manage their file-systems using LVM. It is recommended for students to read the following resource prior to this lab and/or return to the following resource while performing this lab: Logical Volume Management

At this point, having completed Lab 2 you should have roughly the following disk storage setup:
(Note: These results are output from the vgs, lvs, and pvs commands that provide volume group, physical volume and logical volume information for each of the virtual machines that you created in lab2. Before proceeding, check these values with your own system to see if you are generally "on the right track".

  • fedora1
 VG         #PV #LV #SN Attr   VSize VFree
 vg_fedora1   1   2   0 wz--n- 9.50g    0
 PV         VG         Fmt  Attr PSize PFree
 /dev/vda3  vg_fedora1 lvm2 a--  9.50g    0
 LV      VG         Attr   LSize Origin Snap%  Move Log Copy%  Convert
 lv_root vg_fedora1 -wi-ao 8.03g                                     
 lv_swap vg_fedora1 -wi-ao 1.47g 
  • fedora2
 VG         #PV #LV #SN Attr   VSize  VFree
 vg_fedora2   1   3   0 wz--n- 14.50g 3.25g
 PV         VG         Fmt  Attr PSize  PFree
 /dev/vda3  vg_fedora2 lvm2 a--  14.50g 3.25g
 LV      VG         Attr   LSize Origin Snap%  Move Log Copy%  Convert
 lv_home vg_fedora2 -wi-ao 1.97g                                     
 lv_root vg_fedora2 -wi-ao 7.81g                                     
 lv_swap vg_fedora2 -wi-ao 1.47g 
  • fedora3 (Note: This VM has no GUI installed)
 VG         #PV #LV #SN Attr   VSize VFree
 vg_fedora3   1   3   0 wz--n- 9.51g    0
 PV         VG         Fmt  Attr PSize PFree
 /dev/vda3  vg_fedora3 lvm2 a--  9.51g    0
 LV      VG         Attr   LSize   Origin Snap%  Move Log Copy%  Convert
 lv_home vg_fedora3 -wi-ao   1.00g                                     
 lv_root vg_fedora3 -wi-ao   8.00g                                     
 lv_swap vg_fedora3 -wi-ao 520.00m                                     

  • f17host (i.e. "removable hard disk" or "disk pack")

Does not use LVM. Confirm this using the same commands used above.

Note.png
VM Backups and Recovery
Most of these investigations will take place in your virtual machines. If you make a significant mistake, your virtual machine may not boot. Remember that you created backups of your virtual machines in Lab 2, and you can restore them if something goes wrong.

Remember: if you did not create backups for all of your VMs, then you don't have any restoration points to fall-back to!

Investigation 4: Extend the size of lv_root using command-line tools

Perform this investigation in fedora3.

Let's say that you have run out of disk space on your computer (fedora3), you need more space on the root filesystem, perhaps to host more webpages or a larger database or new software. What are your options? Getting a replacement harddrive would probably require reinstallation of the operating system and backup/restore of the data.

Because we're using LVM though - we can avoid that. We can add a new harddrive (which will serve as a physical volume) to the volume group, and extend the root logical volume to make use of the new available space.

Perform the following operations to increase the size of lv_root in fedora3:

Steps:

  1. Run the following commands and make note of the output:
  2.  ls /dev/vd*
     pvs
     vgs
     lvs
     df -h
    
  3. Open the fedora3 virtual machine console
  4. Go to the hardware details view
  5. Click "Add Hardware" and add a new storage device of 2GBs, make sure it's a VirtIO disk.
  6. Go back to the console view
  7. Run the same ls command now, what's changed?
  8. Now we'll make the new device as a physical volume, add it to the volume group, and extend lv_root:
  9.  pvcreate /dev/vdb
    
     vgextend vg_fedora3 /dev/vdb
    
     lvextend -l +100%FREE -r vg_fedora3/lv_root
    
  10. Now rerun the ls/pvs/vgs/lvs/df commands. What has changed and what caused those changes?
  11. Among the changes, note that your root filesystem is now 2GB bigger - and you have not even rebooted your machine!

Answer the Investigation 4 observations / questions in your lab log book.

Investigation 5: How are LVMs managed using system-config-lvm?

Perform this investigation on the VM named fedora2.

Screenshot of system-config-lvm in Fedora. Click to enlarge.
  1. Let's learn to administer (manage) our LVM graphically for our Fedora2 Virtual Machine.
    Fedora provides a tool called system-config-lvm to graphically administer LVM. It will appear on the menu as Application>Other>Logical Volume Management. The package may not be installed by default, so you will need to install it by issuing: (yum install system-config-lvm).
  1. Use this tool to determine the current LVM configuration by clicking on the appropriate element and reading the properties in the right-hand panel -- write down the answers:
    1. What are the names and sizes of the PVs?
    2. What is the name and size of the VG?
    3. What are the names and sizes of the LVs?
    4. Is there any space in the VG which is not allocated to a LV?
  2. Increase the size of the home file-system to 2 GB:
    1. Click on the LV containing the home filesystem.
    2. Click on Edit Properties.
    3. Change the size to 2 GB and click Ok.
  3. Create a new 2G LV (LV Properties: linear) containing an ext4 filesystem named lv_archive and mount it at /archive
    1. Click on Logical View.
    2. Click the Create New Logical Volume.
    3. Set the name, size, filesystem, and mount point.
    4. Click Ok.
  4. Backup /etc into /archive
  • Copy the files in /etc into the filesystem mounted at /archive
    (use the graphical tools or the command line. If using cp, remember to use the -R option).
  1. Shrink the size of lv_archive to 1 GB.
  2. Try shrinking the home file-system. What happens? Why?

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

Updated backup instructions

If you completed this lab correctly - please make sure you are still making full backups of your virtual machines.

Remember adding a new harddrive to fedora3? You will need to back up that drive as well. If you don't - you will only have half of your machine backed up, which is of no use for a recovery.

Completing the lab

Important.png
Time for a new backup!
If you have successfully completed this lab, make a new backup of your virtual machines.

Notes:

  1. rpm command options
  2. yum command options
  3. How to use pvs/vgs/lvs/df/pvcreate/vgextend/lvextend
  4. Answer to this question "What is the license of the nautilus package?"

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. nled installed on the host (disk pack - main system f16host).
  2. Unnecessary/unused packages have been deleted (list at least 4, and show that they are no longer installed).
  3. Fresh backup of the virtual machines.

Preparing for Quizzes

  1. What is a VG? PV? LV?
  2. What commands are used to determine VG / PV / LV information?
  3. What does yum do that rpm does not?
  4. List the steps to install a package via rpm command.
  5. List the steps to determine detailed information regarding an install package.
  6. List the steps to remove a package via rpm command.
  7. List the steps to install a package using the yum command.
  8. List the steps to remove a package using the yum command.
  9. What is the total size of the "main" VG on your system?
  10. How do you create a LV?
  11. How do you delete an LV?
  12. How would you increase the size of the root filesystem by 50 MB?