[[Category:OPS235]]{{Admon/caution|THIS IS AN OLD VERSION OF THE LAB|'''Bold textThis is an archived version. Do not use this in your OPS235 course.'''}} 

:* '''Correctly install the CentOS 7 FULL INSTALL DVD''' (not LIVE DVD) on your removable hard disk. * '''Record installation characteristics of CentOS 7 FULL INSTALL''' in a chart (contained in lab2 logbook chart) to compare with other installation methods performed in lab2.

:* '''Verify correct settings''' prior to proceeding with host installation stages.

:* '''Obtain Linux server information after installation''' to create a software asset report for later access.

:* '''Disable Linux Kernel security enhancements''' to allow easier internal networking connections (to be reactivated in a later lab).

:* Observe that '''Bash Shell Scripts can automate routine tasks'''.

==Minimum Required Materials / Lab Preparation=={|cellpadding="15" width="100%"

| [[Image:blank-cd.png|thumb|left|75px|<b>CentOS 7</b>FULL INSTALL DVD]]

| [[Image:harddrive.png|thumb|left|75px|<b>Removable Hard Disk Pack</b> (SATA)]]

|[[Image:ubs-key.png|thumb|left|75px|<b>USB key</b><br>(for backups)]]

|[[Image:log-book.png|thumb|left|60px|<b>Lab Log Book</b><br>(labs 1 & 2)]]

|width="40%" |{{Admon/tip|Access to Instructions for Lab1|Since you will performing a full install on your computer, you cannot use that computer to simultaneously view instructions while you perform the full install. Here are some suggestions to make this process easier:<ul> <li>'''Printout Lab1 instructions''' at home prior to performing Lab1</li> <li>'''Use a smart-phone, notebook, or netbook computer to view lab instructions''' (highly recommended)</li><li>If lab space availability is not an issue, '''use another computer termimal to view lab instructions''' while performing install</li><li>'''Follow step-by-step instructions from your OPS235 instructor''' (if demonstrated by instructor)</li></ul>|

==My Toolkit (CLI Reference)== {|width="100%" cellpadding="5"

[http://www.rpm.org/max-rpm/rpm.8.html rpm]<br>[http://man7.org/linux/man-pages/man8/yum.8.html yum]

[http://man7.org/linux/man-pages/man1/wc.1.html wc]<br>[http://man7.org/linux/man-pages/man1/pwd.1.html pwd]<br>[http://man7.org/linux/man-pages/man1/ls.1.html ls]<br>[http://man7.org/linux/man-pages/man1/more.1.html more]<br>[http://man7.org/linux/man-pages/man1/file.1.html file]<br>[http://man7.org/linux/man-pages/man1/wget.1.html wget]<br>[http://man7.org/linux/man-pages/man1/chmod.1.html chmod]<br>[http://man7.org/linux/man-pages/man1/scp.1.html scp]<br>[http://ss64.com/vi.html vi] |width="40%"|{{Admon/tip|Online Hands-on Linux Command ReviewTutorials (recommended)|The following links online tutorial will allow you to practice Linux commands that you learned from ULI101as well as essential shell scripting skills. Login to your '''Matrix''' account, and issue the pathnames to run the online tutorial in Matrix:<br><ul> <li>Bash Shell CommandUsing the vi Text Editor:<br>'''/home/murray.saul/vi-line Editingtutorial'''</libr><li>Common Linux CommandsBasics:<br>'''/home/murray.saul/li><li>Using a Text Editorlinux-basics'''</li><li>Simple Bash Shell Scripting- Part I (Scripting Basics):<br>'''/home/murray.saul/scripting-1'''</li></ul>|

{{Admon/important |You're supposed For the next 3 investigations, you will learn how to use this install your Centos Full DVD onto your removable hard drive only for this course| But if you really need disk. You will customize your install to use it for two courses, and the professor for the other setup several separate partitions:<ul><li>'''/''' (The "root" partition)</li><li>'''/home''' (Store regular user accounts)</li><li>'''/var/lib/libvirt/images''' (probably windowsstore virtual machine images to be created in lab2) </li><li>'''swap''' course will allow it - ask partition (Virtual Memory)</li></ul> Make certain to record your professor observations of this install in the comparison chart for help with partitioning'''c7host''' in your lab2 logbook.}}

   ::'''<u>Host Machine Details:</u>''' ::*'''Name:''' c7host::*'''Boot media / Installation:''' CentOS7 Full Install DVD::*'''Memory:''' 16GB::*'''Disk space:''' 250GB (or higher)::*'''CPUs:''' 1 {| width="40%" align="right" cellpadding="10"|- valign="top"|colspan="2"|{{Admon/important |You're supposed to use this hard drive only for this course| But if you really need to use it for two courses, and the professor for the other (probably windows) course will allow it - ask your professor for help with partitioning.}}|- valign="top"|[[Image:lab2-logbook.png|thumb|right|100px|'''comparison chart''' in lab2 logbook.]]|[[Image:installation_summary.png|thumb|right|500px400px|The <b>'''Installation Summary ''' screen</b> provides flexibly when configuring to install on your computer. ]]|} # For Refer to this listing of installation screenshots if you need a reference: <ulbr><li>Installation Pictures: [ [http://matrix.senecac.on.ca/~murray.saul/ops235/installation/ installation screenshots] ]</li><li>Installation Streaming Video: [ ]</li></ul><br>

# Restart the '''Newer computer, and models''' are labelled '''press the function key F10, press ENTER, and specify the device to bootHP Z230''' (eg. DVD drive). :<br><br>'''NOTES:'''NOTE:<ul><li>If you are using the '''<u>newer</u>''' model, allow the computer to boot up (<u>without</u> pressing F10 key) to boot from DVD.</li><li>Refer to the comparison chart in lab2 lab logbook, and fill in various installation information for '''c7host''' while you perform the installation (such as time it took to perform a full install, installation options, etc).<br><br></li></ul>

<li value="56">Select Power on the option computer again, and after booting from the CD, select from the installation menu: '''Test this Media & Install Centos7'''. Your DVD will be checked for defects<br><br>Note: If you experience unreadable display after you boot into your installed system, you can redo the install, but select from the install menu: ''<u>Troubleshooting</u>'' and then select ''<u>Install in Basic Graphics Mode</u>''.<br><br></li> <li>If the check is successfulNext, you will be prompted for a language. In the first screen, select language '''English''' with subselection '''English-Canada''' and then click the '''Continue''' button on the bottom right-hand screen.</li>

<li>Configure the following installation settings from the ''Install Summary Screen'':<br><br><b>DATE & TIME:</b><ul><li>Click on the Map to select Toronto area (you may also select from the drop-down menu section)</li><li>Click the <b>DONE</b> button at the top-right left corner to finish and return to the Installation Summary screen.</li></ul><br><b>NETWORK & HOSTNAME:</b><ul><li>Select the default Ethernet connection and click the button on the top right-hand side to change the setting from <b>OFF</b> to <b>ON</b>.</li><li>At the bottom rightleft-hand corner type the hostname: <b>c7host</b> (all lowercase letters)</li><li>Review your settings, then click the <b>DONE</b> button at the top-right left corner to finish and return to the Installation Summary screen.</li></ul><br><b>SOFTWARE SELECTION:</b><ul><li>Select the software packages labelled: <b>Gnome Desktop</b></li><li>Click the <b>DONE</b> button at the top-right left corner to finish and return to the Installation Summary screen.</li></ul><br></li> <li>Although the Centos installtion program can provide suggestions on how to partition your hard disk, you will be customizing partitions for your hard disk. This custom partitioning is important since it will have consequences on future labs that you perform (especially for lab2!).<br><br>Proceed to '''Part 2''' to customize your partitions.</li>

#In the installation destination screen, select the destination option: '''I will configure partitioning'''and then click '''Done'''.#The manual partitioning screen should appear.#If you have used your hard disk for previous Linux (Centos) distributions, you should remove them. Click on the distribution, and for each partition, select the partition and click the remove button (minus sign) and confirm deletion.#<span style="background-color:yellow">Change the option '''New mount points will use the following partition scheme''' from '''LVM''' to '''<u>Standard Partition</u>''' (you will not be using LVM for your c7host machine)</span>.#Before you proceed with creating partitions, let's see the partitions that we need to create for our host computer:<ul><li>Primary Partitions (ext4):<ul><li>'''30GB''' for '''/''' (i.e. "root")</li><li>'''40GB''' for /home</li><li>'''100GB''' for '''/var/lib/libvirt/images''' </li></ul> </li><li>Swap Partition:<ul><li>'''16GB''' (Note: "swap" must be selected from the drop down menu)</li></ul></li></ul><br>'''NOTE:''' Remember that the sizes are recorded in MB (eg. 30 GB = 30000 MB) and you should multiply GB by a factor of 1024 to get the correct size.<br> (eg. '''30 GB x 1024 = 30720 MB''')<br><br>#We will now create the root (/) partition. '''Click on the add button (plus) sign'''.<br>#In the '''Add a New Mount Point''' screen, select '''/''' as the mount-point (either by typing or selecting from drop-down menu), and enter '''30720''' in for partition size and click '''Add Mount Point''' button.# You will return to the previous dialog box.<br><span style="background-color:yellow">For the '''/''' partition, change the file-system type from '''xfs''' to '''ext4''' and make certain that the Device Type is set to Standard Partition (<u>not</u> LVM). You need to repeat this procedure for the ''/home'' and ''/var/lib/libvirt/images partitions'' as well)</span>.#Repeat the same steps above for the '''/home''' partition and '''/var/lib/libvirt/images''' partition. You need to type the ''/var/lib/libvirt/images'' partition since it does not appear in the drop-down menu.#Recheck each of the created partitions, and make certain that the file-system type is set to ''ext4'' and the Device Type is set to ''Standard Partition''.#Finally, add a swap partition (Mount Point: swap) for '''16 GB'''.#Check that your partition settings are correct (you can ask your instructor or lab monitor to confirm), and then click '''Done''' (possibly '''<u>twice</u>''') in order to proceed<br><br><span style="background-color:yellow">'''NOTE:''' If there is an error message associated with your created partitions, you may need to add a '''/boot/efi''' partition (as a new mount). The capacity should be: 2954MB (i.e. 2,954 MB). Once finished, click '''Done'''.<span><br><br>#A Summary of Changes screen will appear to show the partitioning operations that will be created. Click the '''Accept Changes''' and click '''Begin Installation''' in the Installation Summary screen to proceed with the installation.#Start timing your host machine installation.

 <ol> <li>If you get a warning with something like {|width="This device may contain data40%" - it's probably your new hard drive and you can safely use it.</li> <li>Select '''Create Custom Layout''', we don't want to use the default setup now. If you are using a hard drive that contains partitions from a previous course (previous version of Linux), delete all partitions prior to proceeding.</li> <li>On your drive you will need the following partitions. These may be primary partitions or logical drives.<br>Remember that the sizes are recorded in MB (eg. 20 GB align= 20000 MB) and you should multiply GB by a factor of 1024 to get the correct size (eg. '''20 GB x 1024 "right" cellpadding= 20480 MB''')<br> If you have more space than 250GB available - you can add the extra space in equal parts to /home and /var/lib/libvirt/images</li> <ul><li>Primary Partitions (ext4): <ul> <li>'''20GB''' for '''/''' (i.e. "root10")</li> <li>'''30GB''' for /home</li> <li>'''100GB''' for '''/var/lib/libvirt/images''' </li> </ul> </li> <li>Swap Partition: <ul> <li>'''8GB''' (Note: |- valign="swaptop" must be selected from the drop down menu)</li> </ul></li> </ul></li> <li>x</li> <li>Record briefly in your lab logbook what partitions you created of what size and what device names were assigned to them (/dev/sda1, etc.).</li> <li>After confirming partition settings, click next and select '''write changes to disk'''. The installation program will create and format the partitions.</li> </ol>|{{Admon/tip|Linux File System Types|Similar to other Operating Systems, it is good to know basic characteristics of file system types in Linux to select the best type for your machine:<br><ul><li><b>xfs:</b> &nbsp; Newer filesystem (fast transfer rates for large files, Journaling)</li><li><b>ext4:</b> &nbsp; Newer filesystem supporting large files and Journaling</li><li><b>ext2:</b> &nbsp; Stable filesystem popular for databases (no journaling)</li></ul>|}} [[Image:partition_verificationcompleted.png|thumb|right|500px|Carefully verify partition mount-names This screen indicates that installation is complete. You should remove the install DVD and sizes prior to proceeding with install. Check [http://matrix.senecac.on.ca/~murray.saul/ops235/installation/ installation screenshots] link for verificationconfirm Centos7 boots from your removable hard drive.]]

== Part 3: Complete Installation = Turn-Off Screen Saver Lock ===[[Image:completed.png|thumb|right|500px|This screen indicates that installation is complete. You should remove the install DVD and confirm Centos7 boots from your removable hard drive. ]]<ol> <li>Accept the default settings to create the Bootloader and click next.</li> <li>Make certain that '''Desktop''' applications have been selected, and accept the default settings in the '''additional repositories''' section (at the bottom), then proceed. You may look at what's available if you choose "Customize now" but you don't need to customize the software installed at this point.</li> <li>Add in your lab logbook a brief description of the term "software repository" and what its major purpose serves (what you think it does). We will not add any existing repositories since we are not currently connected to the Internet. Therefore, we will customize the repositories later.</li> <li>'''Proceed with the installation. This may take some time'''. Record in your lab log-book the <u>general</u> steps in the installation process (displayed in the dialog box).</li> <li>When installation is complete, a screen will confirm completion, and will then ask the user to remove the DVD, and reboot the computer. Write in your lab log-book the time it took to perform this DVD install.</li> <li>Remove the Installation DVD, and click '''Reboot'''.</li>  <li>Remember to press F10 when restarting the computer, and select the your SATA drive to boot from your removable hard drive.</li> <li>When the system starts, a one-time setup program will run to add regular user accounts, and to set date and time.</li> <li>Create a user account for yourself using the same user ID as your learn account, and create a suitable password.</li> <li>Set or accept the time and date default. Normally, you would want to enable '''Network Time Protocol''', but since we will be experimenting with the networking turned off in later labs, '''leave it disabled'''.</li> <li>Accept all other defaults (you can ignore the Kdump feature). Finish the post-installation customization and then login to your computer account that you created.</li> <li>Proceed to Investigation 2</li> </ol> '''Answer Investigation 1 observations (all parts and questions) in your lab log book.'''

=INVESTIGATION 2: OBTAINING HOST MACHINE SYSTEM INFORMATION=Your system automatically enables a '''screen-saver''' application which is a useful security tool to prevent unauthorized viewing of information on a terminal after a certain amount of inactivity.

After switching user notice and make note of the change in your shell prompt. Also note the difference in output for the <codeol>whoami</codeli value="14"> andProceed to Investigation 2 to obtain basic information from your newly installed Centos Host machine.<code/li>pwd</codeol> commands.

'''Whenever this is required, make a note of it, Answer Investigation 1 observations (all parts and determine why superuser privilege is requiredquestions) in your lab log book.'''

In some documentation, you may see the command <code>su -</code> used in place of <code>su</code>. The dash argument causes <code>su</code> to go through the steps that would normally be performed when the root user logs in, including (1) running the startup scripts (such as<code>/etc/profile</code> and <code>/root/.bash_profile</code> and (=INVESTIGATION 2) changing to the root user's home directory (<code>/root</code>).: OBTAINING HOST MACHINE SYSTEM INFORMATION=

# The With older (ancient) versions of Linux, a user once may have been allowed to login to their graphical Linux system using '''root''' as their user-name of and their root password. This has been determined to be a security risk and that option has been removed with many or all Linux operating systems.#Therefore, from this point onwards, you will be logging into your regular user account instead and issuing a command to login as the ''root'' user. #Refer to the Information box regarding how to access the admin account from the command line.#Issue the installation log file is command <b><code><span style="color:#3366CC;font-size:1.3em;">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:1.3em;">su - </span></rootcode></installb> Issue the '''pwd''' and '''whoami''' commands to confirm your directory pathname.logWhat do you notice are the main differences between using '''su''' versus using '''su -'''?# An installation log file called <b><code><span style="color:#3366CC;font-size:1.2em;">/var/log/anaconda/packaging.log</span></code> -- It </b> has been created to record the installation of your c7host machine. This file is an ASCII file (how can you be sure?) which can be viewed with the <b><code>'''less'''<span style="color:#3366CC;font-size:1.2em;">more</span></code></b> command.

:: <b><code>'''<span style="color:#3366CC;font-size:1.2em;">grep ________________ ________________ -i packaging /var/log/anaconda/packaging.log | wc -l'''</span></code></b>

<li value="38">Issue that command displayed above. Does it work? If not, what account do you think you should be in? When you get the command working record this important information regarding commands and the admin account in your lab logbook.</li> <li>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>

:: <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>

<li value="410">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>installpackaging.log</code>), you can list all the files that were installed from the package by using the following command:</li>

:: <b><code>'''<span style=" pointer-events:none;cursor:default;color:#3366CC;font-size:1.2em;">rpm -q -l package_name'''gedit</span></code><br /b> <ol><li value="12">(where '''package_name''' represents Issue the following command to obtain the name total number of the ''application'' or ''package'')files installed for gedit:<br><br></li></ol>::<b><code><span style=" pointer-events:none;cursor:default;color:#3366CC;font-size:1.2em;">rpm -ql gedit | wc -l</span></code></b>

<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>:: <code>'''rpm -ql package_name| wc -l'''</code><ol> <li value="813">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><li>How can you explain why this number is a lot larger than the total number of packages installed? Record your answer in your lab logbook.

==Part2: Obtaining System and Network Information==

<ol>{|width="40%" align="right" cellpadding="10"|- valign="top"|{{Admon/important|Pathname for USB Stick|The default mount location has been changed in linux distributions newer than CentOS. So while we will get '''/media/usb-device-name''', in newer distributions you'll see '''/run/media/userloginid/usb-device-name'''}}|}<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></lib><li>#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></lib><li>#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.#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 ''nslookup''prompt, enter the word ''ps -ef'server'''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</lispan></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><livalue="9">To capture Run the list of all commands <b><code><span style="color:#3366CC;font-size:1.2em;">hostname</span></code></b>, <b><code><span style="color:#3366CC;font-size:1.2em;">uname -rv</span></code></b>, <b><code><span style="color:#3366CC;font-size:1.2em;">ps -ef</span></code></b>, <b><code><span style="color:#3366CC;font-size:1.2em;">ifconfig</span></code></b>, and <b><code><span style="color:#3366CC;font-size:1.2em;">route -n</span></code></b> redirecting the system processes output to add to a file in root's home directory called <b><code><span style="color:#3366CC;font-size:1.2em;">system.txt</span></code></b>.</li><li>Copy the installation log file <code>'''ps/var/log/anaconda/packaging.lstlog'''</code>, enter and the command: <code>file '''ps -ef > pssystem.lsttxt''' to a USB memory key, or '''scp'''</code>to your matrix account as a backup.</li></ol>

<ol><li value="13">Copy the installation log file <code>'''/root/install.log'''</code> and Answer the file '''ps.lst''' to a USB memory key, or '''scp''' to your matrix account as a backup.<Investigation 2 observations /li><li>View the section below to learn about and perform an update on questions in your fresh CentOS install (you may have to find spare time to perform this install if you are running short on lab time)log book. '''Do <u>not</u> proceed to Investigation 3 without performing an update'''.</li><li>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 login to SeneNET. Open a terminal and type <code>su</code> to start a shell as root. Enter the command <code>yum update</code> 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).</li></ol>

{{Admon/tip |Rusty Issuing Linux commands since ULI101?|To be an effective Linux administrator, you need to become comfortable on issuing Linux commands in a shell, ==Part 1: Disable SELinux and use resources to quickly learn how to properly formulate Linux commands...<br /><br />You can run the following online tutorials to practice (refresh) issuing Linux commands. These tutorials were designed for another course called "OPS435", but you can still use them for practice. Simply open a shell, SSH into the Matrix server (eg. ssh yourusername@matrix.senecac.on.ca) and run the following 4 tutorials (you can copy and paste these separate pathnames and run like a program):<br /><br />'''/home/ops435/tutorials/tutorial1<br />/home/ops435/tutorials/tutorial2<br />/home/ops435/tutorials/tutorial3<br />/home/ops435/tutorials/vi-tutorial'''<br /><br />You can also refer to the section above called '''Linux Command Online Reference''' to see how use use the following Linux commands to obtain the required information.}}Perform Software Updates==

{|width="40%" align="right" cellpadding="10"|- valign="top"|{{Admon/important|SELinux|SELinux stands for '''Security-Enhanced Linux'''Answer . It is a component that helps to better secure the system to protect against intrusion (hackers). SELinux is enabled upon the Investigation 2 observations 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.}}|}# Disabling SELinux is quite simple, just edit the file '''/ questions etc/selinux/config''' and set SELINUX to '''disable<u>d</u>'''.# Add additional text regarding disabling SELinux.#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. #Make certain that you have at least 30 minutes available in your lab log book-time prior to performing a system update. Never abort a system update since it may damage your system files and render your host mahcine inoperable!#Open a terminal and type <b><code><span style="color:#3366CC;font-size:1.2em;">su</span></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).'''

# 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==Part 2:#* '''ifconfig'''#* '''route -n'''#* '''nslookup''' Automating Routine Tasks (at the > prompt, enter the word "server" (do not type the quotesShell Scripting) and record the output. Type exit to leave nslookup).# Find the following information in the output of the above commands:#* '''MAC address''' of the ethernet network interface#* '''Subnet mask'''#* '''The IP address''' assigned to you by the DHCP server#* '''The default gateway'''#* '''The DNS nameserver'''==

{|width="40%" align="right" cellpadding="10"|- valign="top"|{{Admon/tip|Bash Shell Scripting Tips:|<br><ul><li>'''She-bang line: #!/bin/bash'''Answer <br><br>Shell scripts have evolved of the Investigation past 40 years. To avoid running a newer shell script on an older shell, it is recommended to force running the shell script in the correct shell. In order to do this, on the first line at the very beginning of the shell script, you add the '''#!''' ('''# as in "shhhh" - a comment''', and''' ! is referred to as "bang" run a commmand''': in this case, '''run the command: /bin/bash'''). You can issue the Linux command '''which bash''' to get the correct location. If there is no bash shell on that machine, the shell script will not run (as a precaution - the Linux admin will know how to make a fix to the shell script if required).<br> </li><li>'''Variables:'''<br><br> There are 3 observations types of variables that can be used in shell scripting: '''ENVIRONMENT''' (eg. $USER), '''user-defined''' ($varName), and '''positional parameters''' (eg. $1, $2... containing arguments after shell script or by using set command (eg. '''set $(ls)''' ). Using dollar sign ('''$''') in front of variable expands the value assigned.<br><br></li><li>'''Command Substitution:'''<br><br>A very useful trick to take output from a command to be used as an argument for another command. Examples include:<br>'''file $(ls)'''<br>'''set $(ls);echo $#;echo $*'''<br>'''echo "hostname: $(hostname)"'''<br><br><li>'''Logic Control Flow Statements:'''<br><br>The '''test''' command can be used to see if a condition is true or false<br>(i.e. test $USER &#61; "root") . The '''$?''' special shell variable stores the result (zero if true, non-zero if false). Square brackets '''[ ]''' can be used to represent the test command with the condition <u>inside</ questions in your lab log booku> the brackets (spaces separating brackets).Can use '''if''' / '''if-else''' / '''if-elif-else''' statements with brackets. The '''exit''' command can be used to terminate the shell script with a false value.<br><br>'''<u>Examples</u>'''<br><br>''if [ $USER &#61; "root" ]''<br>''then''<br>&nbsp;''echo "You must be root" >&amp;2''<br>&nbsp;''exit1''<br>''fi''<br><br># For number comparison: use:<br># -gt,-ge, -lt, -le, -eq, -ne<br><br>''if [ $age -gt 65 ]''<br>''then''<br>&nbsp;''echo "retire"''<br>''else''<br>&nbsp;''echo "don't retire"''<br>''fi''<br><br>''if [ $grade -gt 79 ]''<br>''then''<br>&nbsp;''echo "You get Good Mark"''<br>''elif [ $grade -gt 49 ]''<br>''then''<br>&nbsp;''echo "You pass"''<br>''else''<br>&nbsp;''echo "You fail"''<br>''fi''<br></li></ul>}}|}You may have learned about creating and running Bash Shell Scripts in your ULI101 course. Shell scripts help Linux users and system administrators to automate repetitive tasks to become more efficient and to help them save time. You will be reviewing and building a basic Bash Shell script to generate information reports for your newly-installed Linux host machine. Take time to view Shell Scripting Tips which are located on the right-hand side.

= INVESTIGATION 3If you require <u>'''additional practice'''</u> in creating shell scripts and using the vi text editor, run the commands in your '''Matrix''' account: LOOKING AHEAD =<ul><li>'''/home/murray.saul/vi-tutorial'''</li><li>'''/home/murray.saul/scripting-1'''</li></ul>

==Part 1Perform the following steps in your '''c7host''' machine: Disable SELinux==

{{Admon# Make certain to log out of your root account and remain as a regular user.# Open a Shell terminal and use a text editor (such as <b><code><span style="color:#3366CC;font-size:1.2em;">vi</span></code></important|SELinux|SELinux stands for '''Securityb> or <b><code><span style="color:#3366CC;font-Enhanced Linux'''size:1. It is 2em;">nano</span></code></b>) to create a component that helps to better secure the system to protect against intrusion (hackers)Bash Shell script called: <b><code><span style="color:#3366CC;font-size:1.2em;">myreport.bash</span></code></b> in your current directory. SELinux is enabled upon # Copy and paste the default install of CentOStext below into your vi editing session for your file report. SELinux can be a good thing, if bash<br> (how do you take care of it copy 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.}}paste efficiently in Linux?)<br>

<code style="color:#3366CC;font-family:courier;font-size:.9em;margin-left:20px;"><br>&#35;!/bin/bash<br><br>&#35; Author: *** INSERT YOUR NAME ***<br>&#35; Date: *** CURRENT DATE ***<br>&#35;<br>&#35; Purpose: Creates system info report<br>&# Disabling SELinux is quite simple35;<br>&#35; USAGE: ./myreport.bash<br><br>if [ $USER != "root" ] # only runs if logged in as root<br>then<br>&nbsp;echo "You must be logged in as root." >&2<br>&nbsp;exit 1<br>fi<br></code><br><ol><li value="4">Save your editing session, just edit assign the '''myreport.bash''' file read and execute permissions (at least for the owner) and run by typing:<br><b><code><span style="color:#3366CC;font-size:1.2em;">./myreport.bash</span></code></b></li><li>Did it run? If not what do you think you need to do in order to run the Bash Shell Script?</li><li>Issue the command <b><code><span style="color:#3366CC;font-size:1.2em;">su -</span></code></b> and run the script from the regular user's home directory (not root's home directory):<br><b><code><span style="color:#3366CC;font-size:1.2em;">~regularuserid/myreport.bash</span></code></b></li><li> Did it work?</li><li>Reopen your text-editing session for '''~regularuserid/etcmyreport.bash''' and add the following lines of code to the bottom of the shell script file:</ol><br><code style="color:#3366CC;font-family:courier;font-size:.9em;">&#35; Create report title<br><br>echo "SYSTEM REPORT" > /selinuxroot/configreport.txt<br>echo "Date: $(date +'%A %B %d, %Y (%H:%M:%p)')" >> /root/report.txt<br>echo >> /root/report.txt<br></code><br><ol><li value="8">Save and run the bash shell script. View the contents of the file called ' ''report.txt''' that was generated (I hope you are using the up arrow key to issue previously issued commands in order to save time!). Notice how the redirection symbol &gt; is used at the beginning of the report, and set SELINUX then the other redirection symbol &gt;&gt; is used to disabledhelp "grow" the report with the other content.</li><li>The only remaining content of the report would be the system information. We can use a shell scripting trick called "command substitution" $( .. ) in order place results from an command to be used by another command (like echo). Re-edit the shell script and add the following code at the bottom of the shell script file:</li></ol><br><code style="color:#3366CC;font-family:courier;font-size:.9em;">echo >> /root/report.txt<br>echo "Hostname: $(hostname)" >> /root/report.txt<br>echo >> /root/report.txt<br>echo "Kernel Version: $(uname -rv)" >> /root/report.txt<br>echo >> /root/report.txt<br></code><br><ol><li value="10">Save, run the script, and view the ''report.txt'' contents (are you using tip that was given to save time?).</li><li>Edit the shell script and include output from the <b><code><span style=Part 2"color:#3366CC;font-size:1.2em;">ps aux</span></code></b> and <b><code><span style="color:#3366CC;font-size: Automating Routine Tasks 1.2em;">ifconfig</span></code></b> commands (with appropriate titles). Remember to redirect that output to add to the bottom of the file!</li><li>Save, run and confirm that the shell script is working correctly.</li><li>What would be the use of keeping this shell script as a Linux system administrator?</li></ol><ol><li value="14">Here are some more "complex" Bash Shell Scripting)scripts, that perform the same task. Although you are not require to understand some of these other tricks, it is recommended that you view the contents of the scripts and save them for future consideration or exmaples.</li><li>The <b><code>wget</code></b> command can be used to quickly download files from the Internet. Issue the following command:<br><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></li><li>Verify that the file '''text-report.bash''' was downloaded to your current directory.</li><li>Assign read and execute permissions for this file by issuing the command: <b><code><span style="color:#3366CC;font-size:1.2em;">chmod u+rx text-report.bash</span></code></b></li><li>Run this Bash Shell script by issuing the command: <b><code><span style="color:#3366CC;font-size:1.2em;">./text-report.bash</span></code></b></li><li>Check to see if it created a report in your current directory. What is the purpose of the report?</li><li>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></li><li>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></li><li>Try to understand what these Bash Shell scripts do.</li><li>You have completed lab1. Proceed to Completing The Lab, and follow the instructions for "lab sign-off".</li></ol>

= COMPLETING THE LAB / INSTRUCTOR 1 SIGN-OFF (SHOW INSTRUCTOR) =[[Image:lab1_signoff.png|thumb|right|500px|Students should be prepared with a'''ll all required commands (system information) displayed in a terminal (or multiple terminals) prior to calling the instructor for signoff'''.]]

:* '''Installed package count''':* <span style="color:green;font-size:1.5em;">&#x2713;</span> Output of '''lsblk''' command showing correct partition names and sizes:* :<span style="color:green;font-size:1.5em;">&#x2713;</span> Contents of '''/etc/fstab''' file confirming partitions file types are '''ext4'''::<span style="color:green;font-size:1.5em;">&#x2713;</span> Correct '''IP address''' and '''MAC address''':* :<span style="color:green;font-size:1.5em;">&#x2713;</span> '''Default route (gateway)''':* :<span style="color:green;font-size:1.5em;">&#x2713;</span> '''DNS name server IP Address''':* :<span style="color:green;font-size:1.5em;">&#x2713;</span> Contents of your '''myreport.bash''' shell script::<span style="color:green;font-size:1.5em;">&#x2713;</span> proof of '''yum update''' performed on c7host::<span style="color:green;font-size:1.5em;">&#x2713;</span> '''SELinux''' is disabled on '''c7host'''::<span style="color:green;font-size:1.5em;">&#x2713;</span> '''lab1 notes''' <u>and</u> '''first column of Comparison Chart in lab2'''.

= ADDITIONAL PRACTICE = Practice For Quizzes, Tests, Midterm &amp; Final Exam ==

# How many users were created automatically on your system (do not count your learn accountregular, admin)?# What is List 2 ways that you can access your learn root account's UID and GID?# What is your learn accountthe difference between the commands '''su''' and '''su -'''s home directory ?