Difference between revisions of "OPS235 Lab 3 - CentOS7"

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#Boot up your '''centos3''' VM.
 
#Boot up your '''centos3''' VM.
#Change your working directory to <code>/usr/share/doc/sudo*</code>
+
#Change your working directory to <b><code><span style="color:#3366CC;font-size:1.2em;">/usr/share/doc/sudo*</span></code></b>
#Use the tar (tape archiver) command to create an archive file named <code>/tmp/archive1.tar</code>
+
#Use the tar (tape archiver) command to create an archive file named <b>/tmp/archive1.tar</b>
#*<code>tar cvf /tmp/archive1.tar .</code>
+
#*<b><code><span style="color:#3366CC;font-size:1.2em;">tar cvf /tmp/archive1.tar .</span></code></b>
  
 
{{Admon/important | Warning! | Don't miss the '''.''' at the end of the <code>tar</code> commands below! It specifies what should go into the archive: the contents of the current directory.}}
 
{{Admon/important | Warning! | Don't miss the '''.''' at the end of the <code>tar</code> commands below! It specifies what should go into the archive: the contents of the current directory.}}
Line 75: Line 75:
 
   <li>Compress the file using <code>gzip</code>:
 
   <li>Compress the file using <code>gzip</code>:
 
     <ul>
 
     <ul>
       <li><code>gzip /tmp/archive1.tar</code></li>
+
       <li><b><code><span style="color:#3366CC;font-size:1.2em;">gzip /tmp/archive1.tar</span></code></b></li>
 
     </ul>
 
     </ul>
 
   </li>
 
   </li>
Line 81: Line 81:
 
   <li>Make sure you're still in <code>/usr/share/doc/sudo*</code> and then create a compressed archive:
 
   <li>Make sure you're still in <code>/usr/share/doc/sudo*</code> and then create a compressed archive:
 
<ul>
 
<ul>
       <li><code>tar cvzf /tmp/archive2.tgz .</code></li>
+
       <li><b><code><span style="color:#3366CC;font-size:1.2em;">tar cvzf /tmp/archive2.tgz .</span></code></b></li>
 
     </ul>
 
     </ul>
 
   </li>
 
   </li>
   <li>What does the <code>z</code> option do?</li>
+
   <li>What does the <b><code><span style="color:#3366CC;font-size:1.2em;">z</span></code></b> option do?</li>
   <li>Compare the sizes of <code>/tmp/archive1.tar.gz</code> and <code>/tmp/archive2.tgz</code>. Why are they so close in size?</li>
+
   <li>Compare the sizes of <b><code><span style="color:#3366CC;font-size:1.2em;">/tmp/archive1.tar.gz</span></code></b> and <span style="color:#3366CC;font-size:1.2em;">/tmp/archive2.tgz</span></code></b>. Why are they so close in size?</li>
 
</ol>
 
</ol>
  
Line 92: Line 92:
 
===Part 2: Restoring Files From an Archive===
 
===Part 2: Restoring Files From an Archive===
 
{{Admon/note|Remain in your centos3 VM|Perform these steps in the '''centos3''' virtual machine.}}
 
{{Admon/note|Remain in your centos3 VM|Perform these steps in the '''centos3''' virtual machine.}}
#Create the directory <code>/tmp/extract1</code>
+
#Create the directory <b><code><span style="color:#3366CC;font-size:1.2em;">/tmp/extract1</span></code></b>
#Change to the <code>/tmp/extract1</code> directory.
+
#Change to the <b><code><span style="color:#3366CC;font-size:1.2em;">/tmp/extract1</span></code></b> directory.
 
#Move the file archive1.tar.gz to your current directory.
 
#Move the file archive1.tar.gz to your current directory.
 
#Unzip the first archive you created:
 
#Unzip the first archive you created:
#*<code>gunzip archive1.tar.gz</code>
+
#*<b><code><span style="color:#3366CC;font-size:1.2em;">gunzip archive1.tar.gz</span></code></b>
 
#Extract the files from the first archive:
 
#Extract the files from the first archive:
#*<code>tar xvf archive1.tar</code>
+
#*<b><code><span style="color:#3366CC;font-size:1.2em;">tar xvf archive1.tar</span></code></b>
 
#Are all the files there?  
 
#Are all the files there?  
#Compare <code>/tmp/extract1/README</code> and <code>/usr/share/doc/sudo*/README</code>. Are they exactly the same? Why?
+
#Compare <b><code><span style="color:#3366CC;font-size:1.2em;">/tmp/extract1/README</span></code></b> and <span style="color:#3366CC;font-size:1.2em;">/usr/share/doc/sudo*/README</span></code></b>. Are they exactly the same? Why?
#Create the directory <code>/tmp/extract2</code>
+
#Create the directory <b><code><span style="color:#3366CC;font-size:1.2em;">/tmp/extract2</code>
#Move the file archive2.tgz to the <code>/tmp/extract2</code> directory.
+
#Move the file archive2.tgz to the <b>/tmp/extract2</b> directory.
 
#Extract the files from the second archive:
 
#Extract the files from the second archive:
#*<code>tar xvzf /tmp/extract2/archive2.tgz</code>
+
#*<b><code><span style="color:#3366CC;font-size:1.2em;">tar xvzf /tmp/extract2/archive2.tgz</span></code></b>
#Note that this time a separate <code>gunzip</code> command was not needed. Why?
+
#Note that this time a separate <b><code><span style="color:#3366CC;font-size:1.2em;">gunzip</span></code></b> command was not needed. Why?
 
#Repeat the previous command, leaving out the option "z". Does it work? Why?
 
#Repeat the previous command, leaving out the option "z". Does it work? Why?
#Compare the <code>README</code> file in this directory with the original file. Are they exactly the same?
+
#Compare the <b><code><span style="color:#3366CC;font-size:1.2em;">README</span></code></b> file in this directory with the original file. Are they exactly the same?
  
 
'''Answer the Investigation 2 observations / questions in your lab log book.'''
 
'''Answer the Investigation 2 observations / questions in your lab log book.'''
Line 125: Line 125:
 
<ol>
 
<ol>
 
   <li value="3">Go to the directory <code>/tmp</code></li>
 
   <li value="3">Go to the directory <code>/tmp</code></li>
   <li>Use the <code>wget</code> command to download the "tar ball" that contains the source code for the NLED text editor. <code>wget</code> is a command-line tool to download files from the web using the http or ftp protocols.
+
   <li>Use the <b><code><span style="color:#3366CC;font-size:1.2em;">>wget</span></code></b> command to download the "tar ball" that contains the source code for the NLED text editor. <code>wget</code> is a command-line tool to download files from the web using the http or ftp protocols.
 
     <ul>
 
     <ul>
 
       <li><code>wget http://cdot.senecac.on.ca/software/nled/nled_2_52_src.tgz</code></li>
 
       <li><code>wget http://cdot.senecac.on.ca/software/nled/nled_2_52_src.tgz</code></li>
 
     </ul>
 
     </ul>
 
   </li>
 
   </li>
   <li>Extract the files. Change to the newly-extracted directory (<code>/tmp/nled-2.52</code>)</li>
+
   <li>Extract the files. Change to the newly-extracted directory (<b><code><span style="color:#3366CC;font-size:1.2em;">/tmp/nled-2.52</span></code></b>)</li>
   <li>Check to see if there is a file named <code>configure</code>. If so, run it; if not, skip this step. (Most but not all source code archives contain this file)</li>
+
   <li>Check to see if there is a file named <b><code><span style="color:#3366CC;font-size:1.2em;">configure</span></code></b>. If so, run it; if not, skip this step. (Most but not all source code archives contain this file)</li>
   <li>Check to see if there is a file named <code>Makefile</code> or <code>makefile</code>. If so, type the command:
+
   <li>Check to see if there is a file named <b><code><span style="color:#3366CC;font-size:1.2em;">Makefile</span></code></b> or <b><code><span style="color:#3366CC;font-size:1.2em;">makefile</span></code></b>. If so, type the command:
 
     <ul>
 
     <ul>
       <li><code>make</code></li>
+
       <li><b><code><span style="color:#3366CC;font-size:1.2em;">make</span></code></b></li>
       <li>Did the command work? Why? Use the <code>yum</code> command to install the package '''gcc'''. What do you think the package ''gcc'' does?</li>
+
       <li>Did the command work? Why? Use the <b><code><span style="color:#3366CC;font-size:1.2em;">yum</span></code></b> command to install the package '''gcc'''. What do you think the package ''gcc'' does?</li>
 
     </ul>
 
     </ul>
   <li>Reissue the <code>make</code> command. Where you successful? What does <code>make</code> do?</li>
+
   <li>Reissue the <b><code><span style="color:#3366CC;font-size:1.2em;">make</span></code></b> command. Where you successful? What does <code>make</code> do?</li>
   <li>Issue the command as root: <code>yum list ncurses</code>. What do you see? Issue the command at root: <code>yum search ncurses</code>. What do you observe?</li>
+
   <li>Issue the command as root: <b><code><span style="color:#3366CC;font-size:1.2em;">yum list ncurses</span></code></b>. What do you see? Issue the command at root: <code>yum search ncurses</code>. What do you observe?</li>
   <li>In this case, you need to install the ncurses development libraries as well. Issue the following command as root: <code>yum install ncurses-devel.x86_64</code>. Now issue the command: <code>make</code></li>
+
   <li>In this case, you need to install the ncurses development libraries as well. Issue the following command as root: <code>yum install ncurses-devel.x86_64</code>. Now issue the command: <b><code><span style="color:#3366CC;font-size:1.2em;">make</span></code></b></li>
 
   <li>Some software distributed as source code can automatically install itself. Try this command:
 
   <li>Some software distributed as source code can automatically install itself. Try this command:
 
     <ul>
 
     <ul>
       <li><code>make install</code></li>
+
       <li><b><code><span style="color:#3366CC;font-size:1.2em;">make install</span></code></b></li>
 
     </ul>
 
     </ul>
 
   </li>
 
   </li>
 
   <li>Most but not all source code archives include the capability of installing themselves this way.</li>
 
   <li>Most but not all source code archives include the capability of installing themselves this way.</li>
   <li>If the command <code>make install</code> does not work (how can you tell? What command did you learn from ULI101 to confirm that this command cannot be run from the command line?), copy the <code>nled</code> program manually:
+
   <li>If the command <code>make install</code> does not work (how can you tell? What command did you learn from ULI101 to confirm that this command cannot be run from the command line?), copy the <b><code><span style="color:#3366CC;font-size:1.2em;">nled</span></code></b> program manually:
 
     <ul>
 
     <ul>
       <li><code>cp nled /usr/local/bin</code></li>
+
       <li><b><code><span style="color:#3366CC;font-size:1.2em;">cp nled /usr/local/bin</span></code></b></li>
 
     </ul>
 
     </ul>
 
   </li>
 
   </li>
   <li>Test <code>nled</code> to make sure it works.</li>
+
   <li>Test <b><code><span style="color:#3366CC;font-size:1.2em;">nled</span></code></b> to make sure it works.</li>
   <li>Why did copying the nled executable to /usr/local/bin allow the nled command to be run by name anywhere in the command prompt?</li>
+
   <li>Why did copying the nled executable to '''/usr/local/bin''' allow the nled command to be run by name anywhere in the command prompt?</li>
 
</ol>
 
</ol>
  
Line 167: Line 167:
  
 
<ol>
 
<ol>
  <li value="2">Issue the command:  <code>yum install elinks</code> and answer <code>y</code> to the question about installation.
+
  <li value="2">Issue the command:  <b><code><span style="color:#3366CC;font-size:1.2em;">yum install elinks</span></code></b> and answer <b><code><span style="color:#3366CC;font-size:1.2em;">y</code> to the question about installation.
 
   <ol type="a">
 
   <ol type="a">
 
   <li>Where did ''yum'' get the elinks software?</li>
 
   <li>Where did ''yum'' get the elinks software?</li>
Line 174: Line 174:
 
  </li>
 
  </li>
 
  <li>Issue an RPM query to verify that elinks is installed. Record this command in your lab log-book.</li>
 
  <li>Issue an RPM query to verify that elinks is installed. Record this command in your lab log-book.</li>
  <li>Issue the command: <code>yum remove elinks</code></li>
+
  <li>Issue the command: <b><code><span style="color:#3366CC;font-size:1.2em;">yum remove elinks</span></code></b></li>
 
  <li>Issue an RPM query to verify that elinks is no longer installed. Record this command in your lab log-book.</li>
 
  <li>Issue an RPM query to verify that elinks is no longer installed. Record this command in your lab log-book.</li>
  <li>Issue this command: <code>yum info cups</code></li>
+
  <li>Issue this command: <b><code><span style="color:#3366CC;font-size:1.2em;">yum info cups</span></code></b></li>
 
</ol>
 
</ol>
 
::* Based on the result, do you think that cups is a useful package for your system? If not, try removing it.
 
::* Based on the result, do you think that cups is a useful package for your system? If not, try removing it.

Revision as of 12:12, 29 March 2015


LAB PREPARATION

Purpose / Objectives of Lab3

In this lab, you are going to help conserve disk space by learning how to compress and decompress files that are stored on your computer server. In addition, you will learn alternative methods of how to install programs.

Topics include:

  1. Creating and using archive files (tar and tar.gz)
  2. Compiling software packages from source code
  3. Install applications using various methods:
  • Decompressing source code archive, and compiling source code
  • Use yum utility to install software from local programs (on DVD drive)
  • Use yum utility to install software from repositories (online storage areas)
  1. Demonstrating the use of Bash Shell scripts to automate routine tasks


Required Materials / Lab Preparation

CentOS7
FULL DVD
Removable Hard Disk Pack (SATA)
USB key
(for backups)
Lab3 Log Book

My Toolkit (CLI Reference)

Archiving / Compiling:

tar
gzip, gunzip
make

Software Manangement:

rpm
yum

Commands

ls
more
wget
chmod
vi

Idea.png
Online Linux Command Review
The following links will allow you to practice Linux commands that you learned from ULI101:
  • Bash Shell Scripting II: [ ]


INVESTIGATION 1: ARCHIVING FILES

Part 1: Creating a File Archive

Note.png
Use centos3
Perform these steps in the centos3 virtual machine.
  1. Boot up your centos3 VM.
  2. Change your working directory to /usr/share/doc/sudo*
  3. Use the tar (tape archiver) command to create an archive file named /tmp/archive1.tar
    • tar cvf /tmp/archive1.tar .
Important.png
Warning!
Don't miss the . at the end of the tar commands below! It specifies what should go into the archive: the contents of the current directory.
  1. What do the options c, v, and f mean?
  2. Record the archive file size.
  3. Compress the file using gzip:
    • gzip /tmp/archive1.tar
  4. Record the archive file size after compression.
  5. Make sure you're still in /usr/share/doc/sudo* and then create a compressed archive:
    • tar cvzf /tmp/archive2.tgz .
  6. What does the z option do?
  7. Compare the sizes of /tmp/archive1.tar.gz and /tmp/archive2.tgz</code></b>. Why are they so close in size?
  8. </ol>

    Answer the Part 1 observations / questions in your lab log book.

    Part 2: Restoring Files From an Archive

    Note.png
    Remain in your centos3 VM
    Perform these steps in the centos3 virtual machine.
    1. Create the directory /tmp/extract1
    2. Change to the /tmp/extract1 directory.
    3. Move the file archive1.tar.gz to your current directory.
    4. Unzip the first archive you created:
      • gunzip archive1.tar.gz
    5. Extract the files from the first archive:
      • tar xvf archive1.tar
    6. Are all the files there?
    7. Compare /tmp/extract1/README and /usr/share/doc/sudo*/README</code></b>. Are they exactly the same? Why?
    8. Create the directory /tmp/extract2</code>
    9. Move the file archive2.tgz to the <b>/tmp/extract2</b> directory.
    10. Extract the files from the second archive:
      • <b><code>tar xvzf /tmp/extract2/archive2.tgz</code></b>
    11. Note that this time a separate <b><code>gunzip</code></b> command was not needed. Why?
    12. Repeat the previous command, leaving out the option "z". Does it work? Why?
    13. Compare the <b><code>README</code></b> file in this directory with the original file. Are they exactly the same?

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


    Part 3: Compiling Source Code from Archive File

    Now that you know how to create and decompress "zipped tarball archives", we will demonstrate how to install applications from websites containing these types of archives. Although this method is not as "user-friendly" as using the yum or rpm command, this method is useful if the application is NOT contained in regular software repositories...

    Note.png
    Use centos2
    Perform these steps in the centos2 virtual machine.

    In order to build software from source code, you must have the appropriate software development tools (such as make and gcc) and libraries (such as GTK) installed. The required tools will vary depending on the computer languages used in the software being built.

    1. Issue the following command to install a basic set of development tools and libraries:
      <code>yum groupinstall "Development Tools" "Development Libraries"</code>
    Note.png
    Installing Development Libraries
    In the future, remember the above procedure whenever installing software from source. Sometimes, you need to install additional tools or libraries in order to compile a particular software package
    1. Go to the directory <code>/tmp</code>
    2. Use the <b><code>>wget</code></b> command to download the "tar ball" that contains the source code for the NLED text editor. wget is a command-line tool to download files from the web using the http or ftp protocols.
    3. Extract the files. Change to the newly-extracted directory (<b>/tmp/nled-2.52)</li>
    4. Check to see if there is a file named configure. If so, run it; if not, skip this step. (Most but not all source code archives contain this file)
    5. Check to see if there is a file named Makefile or makefile. If so, type the command:
      • make
      • Did the command work? Why? Use the yum command to install the package gcc. What do you think the package gcc does?
    6. Reissue the make command. Where you successful? What does make do?
    7. Issue the command as root: yum list ncurses. What do you see? Issue the command at root: yum search ncurses. What do you observe?
    8. In this case, you need to install the ncurses development libraries as well. Issue the following command as root: yum install ncurses-devel.x86_64. Now issue the command: make
    9. Some software distributed as source code can automatically install itself. Try this command:
      • make install
    10. Most but not all source code archives include the capability of installing themselves this way.
    11. If the command make install does not work (how can you tell? What command did you learn from ULI101 to confirm that this command cannot be run from the command line?), copy the nled program manually:
      • cp nled /usr/local/bin
    12. Test nled to make sure it works.
    13. Why did copying the nled executable to /usr/local/bin allow the nled command to be run by name anywhere in the command prompt?
    14. </ol>

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

      INVESTIGATION 2: Using the Yum Command for Local & Repository Installs

      Part 1: 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 elinks and answer y</code> to the question about installation.
        1. Where did yum get the elinks software?
        2. Why could yum install elinks when rpm couldn't?
        </li>
        
      2. Issue an RPM query to verify that elinks is installed. Record this command in your lab log-book.
      3. Issue the command: <b><code>yum remove elinks</code></b>
      4. Issue an RPM query to verify that elinks is no longer installed. Record this command in your lab log-book.
      5. Issue this command: <b>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 (for example: games, sound & video, etc) 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.

      Part 2: Managing Repositories with Yum

      ADD THIS SECTION

      INVESTIGATION 3: LOOKING AHEAD

      Part 1: Automating Routine Tasks (Shell Scripting)

      x


      1. x

      Answer all observations / questions in your lab log book.

      LAB 3 SIGN-OFF (SHOW INSTRUCTOR)

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

      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:

      Archived files created
      Unnecessary/unused packages have been deleted (list at least 4, and show that they are no longer installed).
      2 packages installed with yum command
      1 repository added for yum
      License of the nautilus package


      Preparing for Quizzes

      1. What is the advantage of disabling services such as bluetooth?
      2. What is the difference between a .tgz file and a .tar.gz file? What do these stand for?
      3. What is the purpose of a repository?
      4. What is source code?
      5. How do you build software from source code?
      6. Which is preferred: installing from an RPM file, or installing from source code? Why?
      7. How do you use service/init/chkconfig to:
        • show/set current runlevel
        • list services
        • stop a service
        • start a service
        • Why is it important to learn how to manage services?
        • Why is it important to stop certain services?