Difference between revisions of "OPS235 Lab 3 - Fedora17"

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[[Category:OPS235]]{{Draft}}
 
 
[[Category:OPS235]][[Category:OPS235 Labs]]
 
[[Category:OPS235]][[Category:OPS235 Labs]]
 
+
{{Admon/caution|THIS IS AN OLD VERSION OF THE LAB|'''This is an archived version. Do not use this in your OPS235 course.'''}}
=OPS235 Lab 3: Logical Volume Management and Software Package Management=
+
=Logical Volume Management and Software Package Management=
  
  
 
==Introduction==
 
==Introduction==
  
:* In this lab, you are going to learn how to properly adjust your various Linux file systems by using and managing LVM both graphically (fedora1, fedora2) as well as command line (fedora3).
+
In this lab you're going to:
 
 
:* Also in this lab, you will learn how to add and remove software packages on your different Linux systems.
 
 
 
 
 
==Objectives==
 
  
#Learn about LVM concepts including Physical / Logical Volumes and Volume Groups.
+
:* Learn how to add and remove software packages on your different Linux systems.
#Learn how to properly resize file-systems using LVM, and understand the consequences to the filesystem due to mistakes.
+
:* Learn how to properly adjust your various Linux file systems by using and managing LVM both graphically (fedora2) as well as command line (fedora3).
#Learn how to add and remove software packages using RPM.
 
  
 +
== Required Materials (Bring to All Labs) ==
  
==Required Materials (Bring to All Labs)==
+
* Fedora 17 LIVE CD
 
+
* Fedora 17 x86_64 Installation DVD
* '''Fedora 16 LIVE CD''' - You can burn this onto a CD-R in the Open Lab
+
* SATA Hard Disk (in removable disk tray)
* '''Fedora 16 x_64 Installation DVD''' - You can burn this onto a DVD-R in the Open Lab (or burn image onto a DVD+R if you are using the Freedom Toaster).
+
* USB Memory Stick
* '''SATA Hard Disk''' (in removable disk tray)
+
* Lab Logbook
* '''USB Memory Stick''' (minimum 64M)
 
* '''Lab Logbook (Lab3 Reference Sheet)''' (to make notes and observations).
 
 
 
  
 
==Prerequisites==
 
==Prerequisites==
  
 
* Completion and Instructor "Sign-off" of Lab 2: [[OPS235 Lab 2]]
 
* Completion and Instructor "Sign-off" of Lab 2: [[OPS235 Lab 2]]
 
  
 
==Linux Command Online Reference==
 
==Linux Command Online Reference==
Line 57: Line 47:
 
*[http://linuxmanpages.com/man8/vgextend.8.php vgextend]
 
*[http://linuxmanpages.com/man8/vgextend.8.php vgextend]
 
|
 
|
*[http://linuxmanpages.com/man8/mkfs.8.php mkfs]
 
 
*[http://linuxmanpages.com/man8/mount.8.php mount]
 
*[http://linuxmanpages.com/man8/mount.8.php mount]
 
*[http://linuxmanpages.com/man8/umount.8.php umount]
 
*[http://linuxmanpages.com/man8/umount.8.php umount]
Line 71: Line 60:
 
:* [http://www.centos.org/docs/5/html/yum/ Using the YUM Utility]
 
:* [http://www.centos.org/docs/5/html/yum/ Using the YUM Utility]
  
=Logical Volume Management=
+
= 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 <u>operational task</u> (like installing or removing a package), using a '''select-option'''
 +
:* What <u>information</u> you want about those packages, using a '''query-option'''
 +
 
 +
'''Perform the following steps:'''
 +
 
 +
# Using information from the man page for <code>rpm</code>, fill in this information:
 +
 
 +
{|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
 +
|
 +
|}
 +
 
 +
'''Answer the Investigation 1 observations / table contents in your lab log book.'''
 +
 
 +
== Investigation 2: How do you install and remove software with RPM? ==
 +
 
 +
# 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>
 +
# Execute the following command: <code>rpm -i lynx-2.8.7-8.fc17.x86_64.rpm</code>
 +
# Issue an RPM query to check that lynx is installed. Record this command in your lab log-book.
 +
# Issue the following command: <code>rpm -e lynx</code>
 +
# Issue an RPM query to verify that lynx is no longer installed. Record this command in your lab log-book.
 +
# Move to the appropriate sub-directory for packages that begin with the letter '''b'''.
 +
# Issue the following command:  <code>rpm -i BackupPC-3.2.1-7.fc17.x86_64.rpm</code> 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''? ==
 +
 
 +
{{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}}
 +
 
 +
# Change to your home directory.
 +
 
 +
<ol>
 +
<li value="2">Issue the command:  <code>yum install BackupPC</code> and answer <code>y</code> to the question about installation.
 +
  <ol type="a">
 +
  <li>Where did ''yum'' get the BackupPC software?</li>
 +
  <li>Why could ''yum'' install BackupPC when rpm couldn't?</li>
 +
  </ol>
 +
</li>
 +
<li>Issue an RPM query to verify that BackupPC is installed. Record this command in your lab log-book.</li>
 +
<li>Issue the command: <code>yum remove BackupPC</code></li>
 +
<li>Issue an RPM query to verify that BackupPC is no longer installed. Record this command in your lab log-book.</li>
 +
<li>Install <code>nled</code> using '''yum'''. Record this command in your lab log-book.</li>
 +
<li>Issue this command: <code>yum info cups</code></li>
 +
</ol>
 +
::* Based on the result, do you think that cups is a useful package for your system? If not, try removing it.
 +
<ol>
 +
<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>
 +
</ol>
 +
 
 +
'''Answer the Investigation 3 observations / questions in your lab log book.'''
  
== Definition of LVM / Check Current LVM Information Prior to Performing Investigations ==
+
=Logical Volume Management (Introduction)=
  
=== Check LVM Information for all Fedora 16 Installs ===
+
== 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.
 
'''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.
Line 82: Line 154:
  
 
'''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]]
 
'''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 <u>roughly</u> the following disk storage setup:<br />
+
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 />
 
('''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 />
 
<u>'''NOTE: Information based on a 250 GB Removable Hard Disk:'''</u>
 
  
 
* '''fedora1'''
 
* '''fedora1'''
Line 127: Line 196:
 
   lv_swap vg_fedora3 -wi-ao 520.00m                                     
 
   lv_swap vg_fedora3 -wi-ao 520.00m                                     
 
   
 
   
  PV        VG        Fmt  Attr PSize PFree
+
* '''f17host (i.e. "removable hard disk" or "disk pack")'''
  /dev/vda2  vg_fedora3 lvm2 a-  9.80G 3.83G
 
 
 
* '''f16host (i.e. "removable hard disk" or "disk pack")'''
 
 
 
  VG        #PV #LV #SN Attr  VSize  VFree
 
  vg_f16host  1  3  0 wz--n- 232.38g    0
 
 
 
  PV        VG        Fmt  Attr PSize  PFree
 
  /dev/sda3  vg_f16host lvm2 a--  232.38g    0
 
 
 
  LV      VG        Attr  LSize  Origin Snap%  Move Log Copy%  Convert
 
  lv_home vg_f16host -wi-ao 176.62g                                   
 
  lv_root vg_f16host -wi-ao  50.00g                                   
 
  lv_swap vg_f16host -wi-ao  5.75g
 
 
 
 
 
{{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 1: Adjusting Sizes of lv_root and lv_home ==
+
Does not use LVM. Confirm this using the same commands used above.
  
=== Why Readjust sizes of lv_root and lv_home? ===
+
{{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!'''|}}
  
If you refer to the LV sizes of your '''f16host''', you may notice that the size of '''lv_root''' (your root system) is quite small compared to the size of '''lv_home'''. The Virtual Machines that you have created are stored in the directory pathname <code>/var/lib/libvirt/images/</code>, and since you are required to make backups and create future VMs (assignments), you will run out of space!
+
== Investigation 4: Extend the size of lv_root using command-line tools ==
  
On the other hand, you may notice that lv_home is extremely large. Therefore, we are going to use LVM management tools to redistribute those logical volume sizes.
+
Perform this investigation in fedora3.
  
{{Admon/caution|LV resize is Required!|You '''MUST''' perform the following steps in order to re size lv_home and lv_root logical volumes. Failure to perform this operation will likely cause the user to run out of space in <code>/var/lib/libvirt/images/</code> directory used to hold future Virtual Machine installations (e.g. assignments).}}
+
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 redistribute the sizes of lv_root and lv_home in f16host:'''
+
'''Perform the following operations to increase the size of lv_root in fedora3:'''
  
 
<u>'''<font>Steps:</font>'''</u>
 
<u>'''<font>Steps:</font>'''</u>
  
# Make certain you are in your '''f16host''' system.
+
<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
  
{{Admon/note|Resizing Logical Volumes While Still in Use|There is a problem when trying to resize lv_home while users are currently logged in. Please note and record the following procedure to resize these volumes. You should research these commands and gain an appreciation of why you are performing these sequence of commands.|}}
+
  vgextend vg_fedora3 /dev/vdb
  
<ol>
+
  lvextend -l +100%FREE -r vg_fedora3/lv_root</code>
<li value="2">Log-off all users on the GUI.</li>
+
  <li>Now rerun the ls/pvs/vgs/lvs/df commands. What has changed and what caused those changes?</li>
<li>Press the keyboard combination '''Ctrl-Alt-F3''' to a switch to a text-based Virtual Terminal</li>
+
  <li>Among the changes, note that your root filesystem is now 2GB bigger - and you have not even rebooted your machine!</li>
<li>Log into your root account (eg. username: ''root'' password: ''admin password'')</li>
 
<li>Enter the following Linux commands:</li>
 
</ol>
 
:: <code>umount /home</code>
 
:: <code>lvreduce -L 20G -r vg_f16host/lv_home</code>
 
:: <code>lvextend -l 100%FREE -r vg_f16host/lv_root</code>
 
:: <code>mount -a</code>
 
:: <code>logout</code>
 
<ol>
 
  <li value="6">Press the keyboard combination '''Ctrl-Alt-F2''' to return to GUI </li>
 
<li>Log into your account.</li>
 
<li>Open a terminal.</li>
 
  <li>Issue the '''vgs''', '''pvs''', and '''lvs''' commands to verify new volume information for your f16host.</li>
 
<li>Proceed to Investigation #1.</li>
 
 
</ol>
 
</ol>
  
'''Answer the Investigation 1 observations / questions in your lab log book.'''
+
'''Answer the Investigation 4 observations / questions in your lab log book.'''
  
 
+
== Investigation 5: How are LVMs managed using system-config-lvm? ==
== Investigation 2: How are LVMs managed using system-config-lvm? ==
 
  
 
'''Perform this investigation on the VM named ''<u>fedora2</u>''.'''
 
'''Perform this investigation on the VM named ''<u>fedora2</u>''.'''
Line 220: Line 270:
 
<ol>
 
<ol>
 
  <li value="6">Shrink the size of <code>lv_archive</code> to '''1 GB'''.</li>
 
  <li value="6">Shrink the size of <code>lv_archive</code> to '''1 GB'''.</li>
  <li>Try shrinking the home file-system. What happens? What would you think would happen if you further reduced the size of your home file-system? </li>
+
  <li>Try shrinking the home file-system. What happens? Why?</li>
 
</ol>
 
</ol>
 
'''Answer the Investigation 2 observations / questions in your lab log book.'''
 
 
 
== Investigation 3: How are LVMs managed using Command-Line Tools?  ==
 
 
'''Perform this investigation on the VM named ''<u>fedora3</u>''.'''
 
 
You are going to repeat the same LVM management operations (as your did with the ''fedora2'' VM), but you will using command-line tools in the '''fedora 3''' VM.
 
 
# Take time to view the following reference for LVM management via command line: [[Logical Volume Management]]
 
 
{{Admon/note|Command Line LVM Reference|Use this resource as a reference when completing this investigation.|}}
 
 
<ol>
 
<li value="2">Write down the exact commands used at each step as well as command output in your Lab3 log-book:
 
  <ol type="a">
 
    <li>Determine the current LVM configuration using the <code>pvs</code>, <code>vgs</code>, and <code>lvs</code> command.</li>
 
    <li>Grow the '''home''' filesystem to '''2G''' using the command <code>lvextend</code>.</li>
 
    <li>Create a '''new 2G LV''' containing an ext4 filesystem and mount it at '''/archive'''. See important note below:</li>
 
  </ol>
 
 
{{Admon/note|Learn How to Learn|Refer to the section called '''Using LVM''' and sub-section '''Filesystems on LVs''' in [[Logical Volume Management]] to complete part "c".|}}
 
 
  <ol type="a">
 
    <li value="4">Reboot your Fedora3 VM to confirm the operation that you performed in the previous step.</li>
 
    <li>Copy the contents of <code>'''/etc'''</code> into <code>'''/archive'''</code></li>
 
    <li>Shrink <code>'''lv_archive'''</code> to '''1G''' (Refer to the section involving reducing file-systems in use [[Logical Volume Management]]. You should be using the commands: <code>umount</code>, <code>resize2fs</code>, <code>lvreduce</code>,  and <code>mount</code>)</li>
 
  </ol>
 
  </li>
 
</ol>
 
 
'''Answer the Investigation 3 observations / questions in your lab log book.'''
 
 
 
== Investigation 4: How can a PV be added to an existing VG? ==
 
 
'''Add an additional 2 GB virtual disk to your ''<u>fedora1</u>'' system, and use it as an additional physical volume:'''
 
# Start <code>virt-manager</code>.
 
# Shutdown ''fedora1'' if it is running.
 
# Open the console window for ''fedora1''.
 
# Select the menu option View>Details.
 
# Click ''Add Hardware'' button at the bottom left-hand corner.
 
# In the ''Adding new virtual hardware'' window that appears, select a Hardware Type of ''"storage"'' and click ''"Forward"''.
 
# Make certain option "Managed or other existing storage" is selected. Click on the ''Browse'' button, then click on ''New Volume''.
 
# Give the new virtual disk file a name of <code>fedora1b</code>, a format of ''raw'', with a ''Max Capacity'' and ''Allocation'' of 2000 MB. Click ''Finish''.
 
# Select the new virtual disk file ''fedora1b.img'' and click ''Choose Volume''.
 
# Select a device type of ''Virtio Disk''.
 
# Finish creating the new virtual disk by clicking ''Forward'' and then ''Finish''.
 
# Boot the system. You should now have both <code>/dev/vda</code> and <code>/dev/vdb</code>.
 
# Record the size of the volume group and the amount of free space <span  class="plainlinks">[http://www.inleds.com/products/?cid=2<span  style="color:black;font-weight:normal; text-decoration:none!important;  background:none!important; text-decoration:none;"> led downlight  singapore</span>](Hint: use a command that you learned in a previous lab).
 
# Partition /dev/vdb with a single partition that fills the whole disk.
 
# Check the messages printed when <code>fdisk</code> exits -- you may need to reboot the system in order for the new partition table to take effect.
 
# Run this command to format the physical volume: <code>pvcreate /dev/''vdb1''</code>
 
# Add the new physical volume to the existing volume group: <code>vgextend ''nameOfVolumeGroup'' /dev/vdb1</code>
 
# Verify that the volume group is larger and has more free space.
 
 
{{Admon/note|Think!|The next part of this investigation is designed to encourage the student to research, think, and use some creativity in working around obstacles in order to solve a task. Research methods can include the Internet searches, etc...}}
 
'''Using that additional space, create a separate filesystem for <code>/home</code>:'''
 
# Create the logical volume <code>lv_home</code> (1G ext4)
 
# Find a way to move the contents of <code>/home</code> onto it.
 
# Change your system configuration so that the new filesystem is mounted on <code>/home</code> from now on.
 
 
{{Admon/tip|SELinux relabelling may be required|Your system may report that the files are not present in the new /home filesystem when they are clearly there. This is due to the Security-Enhanced Linux system (SELinux) preventing access to the files, because the files were tampered with (moved) and are no longer recognized as home directory content. You can fix this problem by restoring the file context labels so that SELinux accepts the files as valid home directory content: <code>restorecon -r /home</code>}}
 
 
'''Answer the Investigation 4 observations / questions in your lab log book.'''
 
 
 
== Investigation 5: How can I use LVM to manage storage on my f16host disk pack? ==
 
'''On your <u>f16host</u> (i.e. "disk pack"), using your choice of the GUI and/or command-line tools:'''
 
# Create a new logical partition ('''NOT a logical volume!''') - minimum 5G, leaving at least 10G free space in the extended partition.
 
# Add that partition as a PV into the existing VG (using the commands you used in the previous investigation).
 
# Grow the root filesystem to fill the available space.
 
  
 
'''Answer the Investigation 5 observations / questions in your lab log book.'''
 
'''Answer the Investigation 5 observations / questions in your lab log book.'''
  
= Software Package Management =
+
= Updated backup instructions =
  
== Investigation 6: How do you query the RPM database? ==
+
If you completed this lab correctly - please make sure you are still making full backups of your virtual machines.
  
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:
+
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.
:* Which packages you want information about, using a select-option
 
:* What information you want about those packages, using a query-option
 
  
'''Perform the following steps:'''
+
= Completing the lab =
  
# Using information from the man page for <code>rpm</code>, fill in this information:
+
{{Admon/important|Time for a new backup!|If you have successfully completed this lab, make a new backup of your virtual machines.}}
  
{|width="100%" border="1" cellpadding="5"
+
'''Notes:'''
|-
+
# rpm command options
!Option
+
# yum command options
!Meaning
+
# How to use pvs/vgs/lvs/df/pvcreate/vgextend/lvextend
!Is this a select-option or a query-option?
+
# Answer to this question "What is the license of the nautilus package?"
|-
 
| -a
 
|Select all packages
 
|select-option
 
|-
 
| -l
 
|
 
|
 
|-
 
| -p ''filename'''
 
|Select this uninstalled package
 
|
 
|-
 
| -i
 
|Show the package license, packager, URL, description, and other general information.
 
|
 
|-
 
| -f '''filename'''
 
|
 
|
 
|-
 
|'''packagename'''
 
|Select just this package
 
|select-option
 
|}
 
 
 
'''Answer the Investigation 6 observations / table contents in your lab log book.'''
 
 
 
 
 
== Investigation 7: How do you install and remove software with RPM? ==
 
 
 
# Change to the directory on your Installation DVD containing the file: <code>lynx-2.8.7-2.fc16.x86_64.rpm</code>
 
# Execute this command: <code>rpm -i lynx-2.8.7-2.fc16.x86_64.rpm</code>
 
# Issue an RPM query to check that lynx is installed.
 
# Issue this command: <code>rpm -e lynx</code>
 
# Issue an RPM query to verify that lynx is no longer installed.
 
# Issue this command:  <code>rpm -i BackupPC-3.1.0-16.fc16.noarch.rpm</code> and note the result
 
 
 
'''Answer the Investigation 7 observations / questions in your lab log book.'''
 
 
 
 
 
== Investigation 8: How do you install and remove software with ''yum''? ==
 
 
 
{{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}}
 
 
 
# Change to your home directory.
 
 
 
<ol>
 
<li value="2">Issue the command:  <code>yum install BackupPC</code> and answer <code>y</code> to the question about installation.
 
  <ol type="a">
 
  <li>Where did ''yum'' get the BackupPC software?</li>
 
  <li>Why could ''yum'' install BackupPC when rpm couldn't?</li>
 
  </ol>
 
</li>
 
<li>Issue an RPM query to verify that BackupPC is installed.</li>
 
<li>Issue the command: <code>yum remove BackupPC</code></li>
 
<li>Issue an RPM query to verify that BackupPC is no longer installed.</li>
 
<li>Install <code>nled</code> using '''yum'''.</li>
 
<li>Issue this command: <code>yum info cups</code></li>
 
</ol>
 
::* Based on the result, do you think that cups is a useful package for your system? If not, try removing it.
 
<ol>
 
<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>
 
</ol>
 
 
 
'''Answer the Investigation 8 observations / questions in your lab log book.'''
 
 
 
 
 
= 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. Remember to also make a backup of the new second virtual disk drive on ''fedora1'' -- you now have two virtual disks on ''fedora1'', and therefore two image files, and therefore will need two backup files.}}
 
  
 
'''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:'''
 
'''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).
# Two PVs on '''fedora1'''.
 
# Separate <code>/home</code> filesystem (on an LV) in '''fedora1'''.
 
# Larger <code>/home</code> on '''fedora2''' and '''fedora3'''.
 
 
# Unnecessary/unused packages have been deleted (list at least 4, and show that they are no longer installed).
 
# Unnecessary/unused packages have been deleted (list at least 4, and show that they are no longer installed).
# Account created on '''fedora3''' matching your Matrix account.
 
# '''nled''' installed on the host (disk pack - main system '''f16host''').
 
# Answer to this question:
 
#* What is the license of the '''nautilus''' package?
 
 
# Fresh backup of the virtual machines.
 
# Fresh backup of the virtual machines.
  
= Preparing for the Quizzes =
+
= Preparing for Quizzes =
  
 
# What is a VG? PV? LV?  
 
# What is a VG? PV? LV?  
 +
# What commands are used to determine VG / PV / LV information?
 
# What does yum do that rpm does not?
 
# 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?
 
# What is the total size of the "main" VG on your system?
 
# How do you create a LV?
 
# How do you create a LV?
 
# How do you delete an LV?
 
# How do you delete an LV?
# How would you add the disk partition <code>/dev/sdb7</code> to your volume group "main"?
 
 
# How would you increase the size of the root filesystem by 50 MB?
 
# How would you increase the size of the root filesystem by 50 MB?

Latest revision as of 11:31, 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?