:* [http://www.centos.org/docs/5/html/yum/ Using the YUM Utility]
= 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 the previous lab you queried that database using RPM with the -q argument. When you query the RPM database, you can separately specify:
:* Do an <u>operational task</u> on one or more packages (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:'''
(Perform investigations 1 - 3 in your host machine (c6host)
# 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'''. It should contain a file called: <code>lynx-2.8.6-27.el6.x86_64.rpm</code>
# Execute the following command: <code>rpm -i lynx-2.8.6-27.el6.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.
# Issue the following command: <code>rpm -i elinks-0.12.rpm</code>. Did it work? Explain in your lab log-book why this command may not have worked.
'''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 elinks</code> and answer <code>y</code> to the question about installation.
<ol type="a">
<li>Where did ''yum'' get the elinks software?</li>
<li>Why could ''yum'' install elinks when rpm couldn't?</li>
</ol>
</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 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>
</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 (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.</li>
</ol>
'''Answer the Investigation 3 observations / questions in your lab log book.'''
=Logical Volume Management (Introduction)=