{{Admon/caution|THIS IS AN OLD VERSION OF THE LAB|'''This is an archived version. Do not use this in your OPS235 course.'''}} =CentOS Installation (on Main Host - c7host)LAB PREPARATION=

<br>[[Image:hostmachine.png|thumb|right|300px|The c7host Linux server will run virtualization software to install and run 3 virtual machines (installed in lab2). ]]You need to install a Linux OS to be a host or "platform" to install and use other Linux VMs (Virtual Machines) during this course. The Linux OS you will be installing in this lab will be a Host Machine (''hostname'': '''c7host''') that will allow you to run '''Virtualization Software''' to create 3 separate virtual machines (to be performed in lab2). It is important to have a install this host machine correctly installed host from since other labs will depend on the installation procecure; otherwise, you may experience problems when performing future labs throughout stability of this coursehost machine. The   <u>main Main objectives</u> for this lab include: * '''Correctly install the CentOS 7 FULL INSTALL DVD''' (not LIVE DVD) on your removable hard disk.

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

:* '''Record installation characteristics of CentOS 7 FULL INSTALLVerify correct settings''' in a chart (contained in lab2 logbook chart) prior to compare proceeding with other host installation methods performed in lab2stages.

:* '''Verify correct settingsObtain Linux server information after installation''' prior to proceeding with host installation stagescreate a software asset report for later access.

:* '''Obtain Disable Linux server information after installationKernel security enhancements''' to create allow easier internal networking connections (to be reactivated in a software asset report for later accesslab).

:* Observe that '''"Turn-off" Linux Kernel security enhancementsBash Shell Scripts can automate routine tasks''' to allow easier internal networking connections (to be reactivated in a later lab).

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

| [[Image:blank-cd.png|thumb|left|100px75px|<b>CentOS 7</b>FULL INSTALL DVD]]

| [[Image:harddrive.png|thumb|left|100px75px|<b>Removable Hard Disk Pack</b> (SATA)]]

|[[Image:ubs-key.png|thumb|left|100px75px|<b>USB key</b><br>(for backups)]]

|[[Image:log-book.png|thumb|left|75px60px|<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|- valign="5" width="50%top"

|[http://unixhelp.ed.ac.uk/CGI/man- valign="top"cgi?grep grep]<br>|[http://linuxmanpagesman7.comorg/linux/man-pages/man8man1/rpmwc.81.php rpmhtml wc]<br>|[http://linuxmanpagesman7.comorg/linux/man-pages/man1/hostnamepwd.1.php hostnamehtml pwd]<br>[http://linuxmanpagesman7.comorg/linux/man-pages/man1/unamels.1.php unamehtml ls]<br>[http://linuxmanpagesman7.comorg/linux/man-pages/man1/psmore.1.php pshtml more]<br>|[http://linuxmanpagesman7.comorg/man8linux/ifconfigman-pages/man1/file.81.php ifconfightml file]<br>[http://linuxmanpagesman7.comorg/linux/man-pages/man8man1/netstatwget.81.php netstathtml wget]<br>[http://linuxmanpagesman7.comorg/linux/man-pages/man8man1/routechmod.81.php routehtml chmod]<br>[http://linuxmanpagesman7.comorg/linux/man-pages/man1/nslookupscp.1.php nslookuphtml scp]<br>|[http://linuxmanpagesss64.com/man1vi.html vi] |width="40%"|{{Admon/tip|Online Hands-on Linux Tutorials (recommended)|The following online tutorial will allow you to practice Linux commands that you learned from ULI101 as 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>Using the vi Text Editor:<br>'''/home/murray.saul/vi-tutorial'''<br><li>Linux Basics:<br>'''/home/murray.saul/linux-basics'''</li><li>Shell Scripting - Part I (Scripting Basics):<br>'''/home/wcmurray.saul/scripting-1.php wc]'''</li></ul>|}}

=== Part 1: Staring Start Installation ===

<ol> <li value="5">Note the time at the beginning of your installation.</li> <li>Select the option '''Install or upgrade existing system''::'. When the Installation DVD boots, it will prompt the user to test the media (i.e. DVD) for integrity. Since time is limited for installation in the lab, select '''SKIP'''. On the other hand, if the install did not work, then you can test out the integrity of the DVD in the computer lab during your spare time.</li> <liu>During the install process the user makes selections, then clicks the '''Next''' button located at the bottom right-hand portion of the screen to continue. Select the default language (English), the default keyboard layout and Basic Storage Devices in the following installation screens.Host Machine Details:</li> <liu>Set your hostname (name of the computer) to '''c6host''' (one word, no space, all lowercase).</li> <li>Set your time zone to '''Toronto'''. Note that the system (BIOS) clock is set to local time, not UTC.</li> <li>'''Root Password:''' enter a password of your own choosing. Pick one that is hard to guess to protect your system. (Recommendation: use the first letter and all the punctuation from a favorite phrase or song verse. For example, "To be or not to be, that is the question!" could become the password "Tbontb,titq!").</li> </ol>

=== Part 2: Partitioning ===:*'''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/tip 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|400px|The '''Installation Summary''' screen provides flexibly when configuring to install on your computer. ]]|}

<li>If you get a warning with something like value="This device may contain data6" - it's probably your new hard drive >Power on the computer again, and you can safely use it.</li> <li>Select after booting from the CD, select from the installation menu: '''Create Custom LayoutInstall Centos7''', 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.</libr> <libr>On your drive Note: If you will need the following partitions. These may be primary partitions or logical drives. Remember that the sizes are recorded in MB (eg. 20 GB = 20000 MB). If experience unreadable display after you have more space than 250GB available - boot into your installed system, you can add redo the extra space in equal parts to install, but select from the install menu: ''<u>Troubleshooting</home u>'' and /var/lib/libvirt/imagesthen select ''<u>Install in Basic Graphics Mode</liu> ''.<ulbr><libr>Primary Partitions (ext4): <ul/li> <li>Next, you will be prompted for a language. In the first screen, select language '''English'''20GBwith subselection ''' for English-Canada''' and then click the '''/Continue''' (ibutton on the bottom right-hand screen.e. "root")</li> <li>The '''30GBInstall Summary''' for /homeshould now appear. This screen allows the installer to customize their Centos7 system prior to installation.</li> <li>Configure the following installation settings from the '''100GB''' for '''/var/lib/libvirt/images'Install Summary Screen'' :</libr> </ulbr> </lib> DATE & TIME:<li/b>Swap Partition: <ul> <li>'''8GB''' Click on the Map to select Toronto area (Note: "swap" must be selected you may also select from the drop -down menusection)</li> <li>Click the <b>DONE</ulb>button at the top-left corner to finish and return to the Installation Summary screen.</li> </ul><br><b>NETWORK & HOSTNAME:</lib><ul> <li>'''Take time Select the default Ethernet connection and click the button on the top right-hand side to carefully verify change the partition information'''setting from <b>OFF</b> to <b>ON</b>. For example</li><li>At the bottom left-hand corner type the hostname: <b>c7host</b> (all lowercase letters)</li><li>Review your settings, if then click the pathname <b>DONE</varb> button at the top-left corner to finish and return to the Installation Summary screen.</li></libul><br><b>SOFTWARE SELECTION:</libvirtb><ul><li>Select the software packages labelled: <b>Gnome Desktop</images is misspelled, you would need to redo lab1!.b></li> <li>Record briefly in your lab logbook what partitions you created of what size Click the <b>DONE</b> button at the top-left corner to finish and what device names were assigned return to them (the Installation Summary screen.</devli></sda1, etc.).ul><br></li> <li>After confirming Although the Centos installtion program can provide suggestions on how to partition settingsyour hard disk, click next and select 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 '''write changes to diskPart 2'''. The installation program will create and format the to customize your partitions.</li>

== Part 2: Custom Partitioning == {|width="40%" align="right" cellpadding="10"|- valign="top"|{{Admon/tip|Mount Points and Linux File System Types|Similar to other Operating Systems like windows '''fat''' / '''vfat''' / '''ntfs''' file system types, it is good to know a few common file system types in Linux for comparison:<br><olul><li><b>xfs:</b> &nbsp; Newer filesystem (fast transfer rates for large files, Journaling)</li> <li>Accept the default settings to create the Bootloader <b>ext4:</b> &nbsp; Newer filesystem supporting large files and click next.Journaling (used in for this lab)</li> <li>Make certain that <b>ext2:</b> &nbsp; Stable filesystem popular for databases (no journaling)</li></ul>|}}|-|[[Image:partition_verification.png|thumb|right|550px|Carefully verify partition mount-names and sizes prior to proceeding with install. Check [http://matrix.senecac.on.ca/~murray.saul/ops235/installation/ installation screenshots] link for verification.]]|}#From the installation summary screen, click '''Installation Destination'''.#In the installation destination screen, select the destination option: '''I will configure partitioning''' and then click '''DesktopDone''' applications .#The manual partitioning screen should appear.#If you have been selectedused your hard disk for previous Linux (Centos) distributions, you should remove them. Click on the distribution, and for each partition, select the partition and accept click the default settings in remove button (minus sign) and confirm deletion.#<span style="background-color:yellow">Change the option '''New mount points will use the following partition scheme'''additional repositoriesfrom '''LVM''' to '''<u>Standard Partition</u>''' section (at the bottomyou will not be using LVM for your c7host machine)</span>.#Before you proceed with creating partitions, then proceed. You may look at whatlet's available if you choose see the partitions that we need to create for our host computer:<ul><li>Primary Partitions (ext4):<ul><li>'''30GB''' for '''/''' (i.e. "Customize nowroot" but you don)</li><li>'''40GB''' for /home</li><li>'''100GB''' for '''/var/lib/libvirt/images''' </li></ul> </li><li>Swap Partition:<ul><li>'''16GB'''t need to customize (Note: "swap" must be selected from the software installed at this point.drop down menu)</li> </ul></li>Add </ul><br>'''NOTE:''' Remember that the sizes are recorded in your lab logbook MB (eg. 30 GB = 30000 MB) and you should multiply GB by a brief description factor of 1024 to get the term "software repository" and what its major purpose serves correct size.<br> (what you think it doeseg. '''30 GB x 1024 = 30720 MB'''). <br><br>#We will not now create the root (/) partition. '''Click on the add any existing repositories since we are not currently connected to button (plus) sign'''.<br>#In the '''Add a New Mount Point''' screen, select '''/''' as the Internetmount-point (either by typing or selecting from drop-down menu), and enter '''30720''' in for partition size and click '''Add Mount Point''' button. Therefore, we # You will customize return to the repositories laterprevious dialog box.</libr> <lispan style="background-color:yellow">For the '''Proceed with /''' partition, change the installation. This may take some timefile-system type from '''xfs''' to '''ext4'''. Record in your lab log-book and make certain that the Device Type is set to Standard Partition (<u>generalnot</u> LVM). You need to repeat this procedure for the ''/home'' and ''/var/lib/libvirt/images partitions'' as well)</span>.#Repeat the same steps in above for the '''/home''' partition and '''/var/lib/libvirt/images''' partition. You need to type the installation process (displayed ''/var/lib/libvirt/images'' partition since it does not appear in the dialog box)drop-down menu.</li> <li>When installation is complete, a screen will confirm completion#Recheck each of the created partitions, and will then ask make certain that the user file-system type is set to remove ''ext4'' and the DVDDevice Type is set to ''Standard Partition''.#Finally, and reboot the computeradd a swap partition (Mount Point: swap) for '''16 GB'''. Write in #Check that your partition settings are correct (you can ask your instructor or lab logmonitor to confirm), and then click '''Done''' (possibly '''<u>twice</u>''') in order to proceed<br><br><span style="background-book the time it took color:yellow">'''NOTE:''' If there is an error message associated with your created partitions, you may need to perform this DVD installadd a '''/boot/efi''' partition (as a new mount). The capacity should be: 2954MB (i.e. 2,954 MB). Once finished, click '''Done'''.</lispan><br> <libr>Remove #A Summary of Changes screen will appear to show the partitioning operations that will be created. Click the Installation DVD, '''Accept Changes''' and click '''RebootBegin Installation'''in the Installation Summary screen to proceed with the installation.</li>#Start timing your host machine installation. == Part 3: Completing the Installation ==

<li>Remember to press F10 when restarting {|width="40%" align="right" cellpadding="10"|- valign="top"|[[Image:completed.png|thumb|right|500px|This screen indicates that installation is complete. You should remove the computer, install DVD and select the your SATA drive to boot confirm Centos7 boots from your removable hard drive.</li>]]|} <li>When #During the system startsinstallation process, a one-time setup program you will run required to add create a '''root password''' (for administration access) and create a '''regular user accounts, account'''. Click on '''Root Password''' and enter your root password. Think of an appropriate password and record that password somewhere in case you forget! An indicator will appear to set date show you how secure your password is. Retype your root password and time.click '''Done''' (you may have to click Done <u>twice</liu>if your password is not considered to be a strong password). <li>Create #You need to create a regular user account for yourself using the same . This account will be used to graphical log into your host machine. It is never recommended to graphically log into a graphical Linux/Unix system as root. It is better to log into a regular user ID account, then run a command to login as root (you will learn how to do this later in this lab).#Click '''User Creation''' and enter your learn account'''full name''', '''username''', and create an appropriate '''password''' (and confirm password). Click '''Done''' to finish (click twice if password is not considered to be a suitable strong password).#<span style="background-color:yellow">Remember to record this host installation information in the '''installation comparison chart''' in the lab2 logbook</lispan>. #When installation is complete, you will notice a message at the bottom of the screen stating: '''CentOS is now successfully installed and ready for you to use!'''#Click the Reboot button. Your DVD will <liu>briefly</u>Set or open in the DVD drive bay. Make certain to remove this installation DVD so that Centos will boot from your hard drive.#After the system reboots, a boot menu should briefly appear, then prompt the user to accept the License Information (this is only a one-time and date defaultoccurrence). Normally<br> In order to accept the license agreement, you would want to enable issue the following keystrokes:<br><br>'''Network Time Protocol1''', but since we will be experimenting with followed by ENTER (to select the networking turned off in later labs, license agreement prompt<br>'''leave it disabled2'''.followed by ENTER (to accept the license agreement)</libr> '''c''' followed by ENTER (to save the selection)<libr>Accept all other defaults '''c''' followed by ENTER (you can ignore a second time to continue booting into the Kdump featuresystem)<br><br>#The system should then graphically prompt the user to login with their regular user account. Finish Click on your '''regular user account name''' and '''enter your regular user password'''.<br><br>#The last phase of the post-installation customization process should now run:<ul><li>Confirm English as the default input source and then login to your computer account that you createdclick '''Next'''.</li> <li>Proceed to Investigation 2Skip the creation of online accounts by clicking '''Next'''.<li>Start using your installed Linux system by clicking '''Start Using CentOS Linux'''.</li></ul><br> #Stop timing your installation and note the amount of time that your installation took to perform. Also take the time to fill in the c7host section of the installation comparison chart in your lab2 logbook.#Open a web-browser and check to see if you can connect to the Internet.</olbr><br>

==Investigation 2: How many file packages and files are installed Your system automatically enables a '''screen-saver''' application which is a useful security tool to prevent unauthorized viewing of information on the system?==a terminal after a certain amount of inactivity.

For the rest of the tasks in :If you find this lab, you must login feature annoying and want to your installed CentOS system using your regular user account (not root), open a terminal and execute turn it off or adjust the idle time perform the following listed Linux commands to obtain information for steps::*Click on your lab'''username at the top right-logbook (lab1). If you get a Permission Denied message when trying to execute a command, then switch to the hand screen''':*Select '''superuserSettings''' account by running from the drop-down menu.:*Click the command '''su -Power''' and type icon located in your password for "root" (which you know since you are the main administrator for your system). Once ''Settings'' Dialog Box:*Change the amount of time in the intended command is executed, type "exit" '''Power Saving''' section to exit from '''Never''' or a '''longer period of time''':*Close the superuser account and return to your regular user account''Settings'' Dialog box.

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>(where '''package_name''' represents the name of the ''application'' or ''package'') <ol> <li value="612">This combines Issue the following command to obtain the total number of files installed for gedit:<code>'''-q'''</codebr> (query) option with the <codebr>'''-l'''</codeli> (list filenames) option</liol> ::<lib>You can pipe the outupt through <code>'''wc <span style=" pointer-l'''</code> to count the number of linesevents:none;cursor:</li></ol>default;color:#3366CC;font-size: <code1.2em;">'''rpm -ql package_namegedit | wc -l'''</span></code></b>

<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>To find out the name that How can you have assigned to your Linux system, enter explain why this number is a lot larger than the command: <code>'''hostname'''</code></li><li>To find out the kernel version total number of packages installed? Record your GNU/Linux workstation and the date it was created, enter the command: <code>'''uname -rv'''</code></li><li>To find out all the system processes running on answer in your GNU/Linux workstation, enter the command: <code>'''ps -ef'''</code></li><li>To capture the list of all the system processes to a file called <code>'''pslab logbook.lst'''</code>, enter the command: <code>'''ps -ef > ps.lst'''''</code></li>

{|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'''}}|}#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><ol/b>#To find out all the system processes running on your GNU/Linux workstation, enter the command: <li valueb><code><span style="13color:#3366CC;font-size:1.2em;">Copy 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 installation output in your log file 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></rootcode></installb>:::<b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.log'''2em;">nslookup</span></code> and </b> (at the file ''nslookup'ps.lst''' to a USB memory keyprompt, or enter the word '''scpserver''' and record the output. Type exit to your matrix account as a backupleave 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<li/span></code></b>View of the section below to learn about and perform an update on your fresh CentOS install 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> (you may have assigned to find spare time to perform this install if you are running short on lab timeby the DHCP server)::: <b><code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1. '''Do 2em;">The default gateway<u/span>not</ucode></b>::: <b> proceed to Investigation 3 without performing an update'''<code><span style="pointer-events: none;cursor: default;color:#3366CC;font-size:1.2em;">The DNS nameserver</lispan></code></b><ol><livalue="9">Run the commands <b><code><span style="color:#3366CC;font-size:1.2em;">hostname</span></code></b>The CentOS software is updated frequently to add features, fix bugs<b><code><span style="color:#3366CC;font-size:1.2em;">uname -rv</span></code></b>, and upgrade security<b><code><span style="color:#3366CC;font-size:1. Perform a system update to get the latest versions of the packages installed2em;">ps -ef</span></code></b>, <b><code><span style="color:#3366CC;font-size: Start the Firefox web browser, turn off popup window blocking (select ''Edit1.2em;">ifconfig</span></code></b>Preferences'', then select the Content tab and uncheck <b><code><span style="color:#3366CC;font-size:1.2em;">route -n</span></code></b> redirecting the box output to Block Popups), then login add to SeneNET. Open a terminal and type file in root's home directory called <b><code>su<span style="color:#3366CC;font-size:1.2em;">system.txt</span></code> to start a shell as root</b>. Enter </li><li>Copy the command installation log file <code>yum update'''/var/log/anaconda/packaging.log'''</code> This will download and install all of the packages that have been updated since the installation DVD image was createdfile '''system. If you complete this command at Seneca it should run quite fast as Seneca College hosts txt''' to a CentOS Repository mirror (a copy of all of the current CentOS packagesUSB memory key, on or '''scp''' to your matrix account as a local web server)backup.</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, 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 />'''Answer the Investigation 2 observations /home/ops435/tutorials/tutorial1<br />/home/ops435/tutorials/tutorial2<br />/home/ops435/tutorials/tutorial3<br />/home/ops435/tutorials/vi-tutorialquestions in your lab log book.'''<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.}}

== Investigation 3Part 1: What is the network configuration? Disable SELinux and Perform Software Updates==

# 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 4If you require <u>'''additional practice'''</u> in creating shell scripts and using the vi text editor, run the commands in your '''Matrix''' account: SELinux ==<ul><li>'''/home/murray.saul/vi-tutorial'''</li><li>'''/home/murray.saul/scripting-1'''</li></ul>

{{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:# Disabling SELinux 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>&#35;<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, 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/myreport.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" > /root/report.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 quite simpleused at the beginning of the report, just and then the other redirection symbol &gt;&gt; is used to help "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="color:#3366CC;font-size:1.2em;">ps aux</span></code></etcb> and <b><code><span style="color:#3366CC;font-size:1.2em;">ifconfig</selinuxspan></configcode></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 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 set SELINUX 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 disabledsee 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>

'''Check off Answer the following items before asking your instructor to check Investigation 3 observations / questions in your lab:log book.'''

= LAB 1 SIGN-OFF (SHOW INSTRUCTOR) =[[Image:lab1_signoff.png|thumb|right|500px|Students should be prepared with '''all required commands (system information) displayed in a terminal (or multiple terminals) prior to calling the instructor for signoff'''.]]'''Arrange evidence (command output) for each of these items on your screen, then ask your instructor to review them and sign off on the lab's completion:'''

* Can login with your ::<span style="learncolor:green;font-size:1.5em;" account name>&#x2713;</span> Output of '''lsblk''' command showing correct partition names and sizes* Has the package count* Has correct ::<span style="color:green;font-size partitions for::* 1.5em;">&#x2713;</span> Contents of '''root /etc/fstab''' (20GB), file confirming partitions file types are '''ext4'''::<span style="color:green;font-size:1.5em;">&#x2713;</homespan> Correct ''' (30GB), IP address'''swapand ''' (8GB):* MAC address'''::<span style="color:green;font-size:1.5em;">&#x2713;</var/lib/libvirt/imagesspan> ''' Default route (100GBgateway)''':* Hint: Can issue <span style="color:green;font-size:1.5em;">&#x2713;</span> '''lsblkDNS name server IP Address''' or ::<span style="color:green;font-size:1.5em;">&#x2713;</span> Contents of your '''blkidmyreport.bash'''shell script* Has the correct IP address and MAC address* Find out the default route (gateway)* IP ::<span style="color:green;font-size:1.5em;">&#x2713;</span> proof of the DNS name server'''yum update''' performed on c7host* Name and contact information ::<span style="color:green;font-size:1.5em;">&#x2713;</span> '''SELinux''' is disabled on your disk pack'''c7host'''* Lag Logbook (::<span style="color:green;font-size:1.5em;">&#x2713;</span> '''lab1) notes filled-''' <u>and</u> '''first column of Comparison Chart inlab2'''.

= Preparing for = 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 ?