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#Exit your current account. Which account are you now using?
#Refer to the Information box regarding how to access the admin account from the command line.
#Issue the command <b><code><span style="color:#3366CC;font-size:1.2em;">su </span></code></b> Issue the '''pwd''' and '''whoami''' commands to confirm your directory pathname. When finished logout of this account.#Issue the command <b><code><span style="color:#3366CC;font-size:1.2em;">su - </span></code></b> Issue the '''pwd''' and '''whoami''' commands to confirm your directory pathname. Remain in this account for the remainder of this lab.
# An installation log file called <code>'''/var/log/anaconda/anaconda.packaging.log'''</code> has been created to record the installation of your c7host machine. This file is an ASCII file which can be viewed with the <code>'''more'''</code> command.
# You can make use of this file to determine how many packages have been installed: complete the following command to count the number of packages that are labelled "Installing" in the installation log file:
:: <b><code><span style="color:#3366CC;font-size:1.2em;">grep ________________ ________________ | wc -l'''</span></code></b>
<ol>
<li value="3">Using the <code>rpm</code> command: you can also use the following commands to list all the installed packages, and the total number of packages installed:</li>
</ol>
::<b><code><span style="color:#3366CC;font-size:1.2em;">rpm -q -a'''</span></code></b>::<b><code><span style="color:#3366CC;font-size:1.2em;">rpm -q -a | wc -l'''</span></code></b>::<b><code><span style="color:#3366CC;font-size:1.2em;">rpm -qa | wc -l'''</span></code></b>
<ol>
<li value="4">The <code>'''-q'''</code> option means query, and the <code>'''-a'''</code> option means all (in other words, query all installed software packages). Did you get the same number of packages from the above two methods?</li>
<li>Some of the files on your system were installed with the software packages, and some were created by system activity (for example, by creating your Learn account and by logging in). If you know the package name (from the <code>install.log</code>), you can list all the files that were installed from the package by using the following command:</li>
</ol>
::<b><code><span style=" pointer-events:none;cursor:default;color:#3366CC;font-size:1.2em;">rpm -q -l package_name</span></code></b><br />(where '''package_name''' represents the name of the ''application'' or ''package'')
<ol>
<li value="6">This combines the <code>'''-q'''</code> (query) option with the <code>'''-l'''</code> (list filenames) option</li>
<li>You can pipe the outupt through <code>'''wc -l'''</code> to count the number of lines:</li>
</ol>
::<b><code><span style=" pointer-events:none;cursor:default;color:#3366CC;font-size:1.2em;">rpm -ql package_name| wc -l</span></code></b>
<ol>
<li value="8">Using what you learned in steps 3, 4, and 7, get a count of the total number of files installed by all of the software packages on your system.</li>
|
#To find out the name that you have assigned to your Linux system, enter the command: <b><code><span style="color:#3366CC;font-size:1.2em;">hostname</span></code></b>#To find out the kernel version of your GNU/Linux workstation and the date it was created, enter the command:<br><b><code><span style="color:#3366CC;font-size:1.2em;">uname -rv</span></code></b>#To find out all the system processes running on your GNU/Linux workstation, enter the command: <b><code><span style="color:#3366CC;font-size:1.2em;">ps -ef</span></code></b>
#We will now collect networking information for your installed system. Your system may not be automatically connected to Seneca's network. Locate the network icon (on top right-hand panel). Click on that icon, and select: '''system eth0'''
# Open a web-browser and log into Seneca's wired network. You will need to perform this set every time you start a new session with your computer to perform future labs.
#Open a shell terminal.
#To check the network configuration settings obtained from the DHCP server, run the following commands, describing the output in your log book:
::: <b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">ifconfig</span></code></b>::: <b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">route -n</span></code></b>:::<b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">nslookup</span></code></b> (at the > prompt, enter the word "server" (do not type the quotes) and record the output. Type exit to leave nslookup).
<ol><li value="8">Find the following information in the output of the above commands:</li></ol>
::: <b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">MAC address</span></code></b> of the ethernet network interface:::<b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">Subnet mask</span></code></b>::: <b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">The IP address </span></code></b> (assigned to you by the DHCP server)::: <b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">The default gateway</span></code></b>::: <b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">The DNS nameserver</span></code></b>
<ol><li value="9">Run the commands '''hostname''', '''uname -rv''', '''ps -ef''', '''ifconfig''', and '''route -n''' redirecting the output to add to a file in root's home directory called '''system.txt'''.</li><li>Copy the installation log file <code>'''/var/log/anaconda/anaconda.packaging.log'''</code> and the file '''system.txt''' to a USB memory key, or '''scp''' to your matrix account as a backup.</li></ol>
# Add additional text regarding disabling SELinux<br><br>
#The CentOS software is updated frequently to add features, fix bugs, and upgrade security. Perform a system update to get the latest versions of the packages installed: Start the Firefox web browser, turn off popup window blocking (select '''Edit''', '''Preferences''', then select the '''Content''' tab and uncheck the box to '''Block Popups'''), then return to your web-browser, load a page, and when prompted, login to SeneNET.
#Open a terminal and type <b><code>su</code></b> to start a shell as root. Enter the command <b><code><span style=" pointer-events:none;cursor:default;color:#3366CC;font-size:1.2em;">yum update</span></code></b> This will download and install all of the packages that have been updated since the installation DVD image was created. If you complete this command at Seneca it should run quite fast as Seneca College hosts a CentOS Repository mirror (a copy of all of the current CentOS packages, on a local web server).
|width="40%" |{{Admon/important|SELinux|SELinux stands for '''Security-Enhanced Linux'''. It is a component that helps to better secure the system to protect against intrusion (hackers). SELinux is enabled upon the default install of CentOS. SELinux can be a good thing, if you take care of it and know how it works. For this course it is strongly recommended that you '''disable SELinux by default''' because we won't have the time to reconfigure it every time the labs make it necessary.}}
[[Image:lab1-script-1.png|thumb|right|175px|When executed as '''root''' or using '''sudo''' command, allows for automatically performing routine tasks such as generating information of a newly installed Linux server]]
#You may have learned about creating and running Bash Shell Scripts in your ULI101 course. Shell scripts help Linux users and system administrators to automatic repetitive tasks to become more efficient and to help them save time.
#The <b><code>wget</code></b> command can be used to quickly download files from the Internet. Issue the following command:<blockquote><b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">wget https://scs.senecac.on.ca/~murray.saul/text-report.bash</span></code></b></blockquote>
#Verify that the file '''text-report.bash''' was downloaded to your current directory.
#Assign read and execute permissions for this file by issuing the command: <b><code>chmod u+rx text-report.bash</code></b>
#Check to see if it created a report in your current directory. What is the purpose of the report?
#Use the <b>vi</b> text editor to view the contents of the file <b>text-report.bash</b>. Can you understand how this script works?<br><br>
#Use the <b><code>wget</code></b> command to download, study, and run the following shell scripts on-line:<blockquote><b><code><span style=" pointer-events:none;cursor:default;color:#3366CC;font-size:1.2em;">https://scs.senecac.on.ca/~murray.saul/report.bash<br>https://scs.senecac.on.ca/~murray.saul/report3.bash</span></code></b></blockquote>
#Try to understand what these Bash Shell scripts do.
#You have completed lab1. Proceed to Completing The Lab, and follow the instructions for "lab sign-off".
