|}
===Managing your Virtual Machine===
In future labs, you will have to run your VMware Workstation application to boot-up your CentOS 7 host VM.Usually, you are NOT required to use this menu (unless you need to "force-off" the c7host7 machine, but should only be performed if you cannot normally shut-down the c7host VM from the OS. On the other hand, there are useful short-cut key you should use: '''ALT-CTRL-ENTER''':Toggles the VM Workstation application window between '''full screen mode''' and '''window mode'''. '''ALT-CTRL''':Return focus from your c7host VM to your '''host computer system'''. '''VMware Tools''' is a collection of utilities to help improve the performance and efficiency of the VM's operating system. Some features include: :* Faster Graphics:* Allow applications running in a VM to be accessed in the host machine (unity interface):* Sharing folders between host and VM:* Copying and pasting text between host and among VMs:* Clock synchronization among host and VMs It is recommended to install VMware Tools on your system. Click the '''VM''' menu and select '''Install VM Tools'''. The installation program will run in the background until the install is complete. {{Admon/caution|Properly Exiting CentOS 7 Session and Safely Removing USB Device|It is '''ABSOLUTELY ESSENTIAL''' that you do '''NOT''' remove your SSD drive during your CentOS 7 session. You are required to correctly shutdown your CentOS 7 host virtual machine as you would with any operating system. Also, you are required to use the '''Safely Remove Hardware and Eject Media''' tool in the system tray on your Windows machine to properly disconnect your SSD device. <br><br>'''FAILURE TO DO THIS MAY DAMAGE YOUR HOST VM AND NOW ALLOW IT TO BOOT PROPERLY (YOU HAVE BEEN WARNED)'''.}} ===Part 1: Turning Off Locked Screen-saver=== 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. Turning-off the locked screen-saver for this (and other) virtual machine can be useful when waiting for your instructor to come over to "sign-off" your computer lab without having to re-issue user passwords. '''To Disable the Locked Screen-saver, Perform the following steps:''' #Click on the '''power button at the top right-hand corner of the window'''.#Click the '''Settings''' icon (bottom left-hand side of menu - looks like a screw-driver and wrench icon.#Click the '''Power''' icon located in the ''Settings'' Dialog Box#Change the amount of time in the '''Power Saving''' section to '''Never''' or a '''longer period of time'''#Close the ''Settings'' Dialog box. ===Part 2: Accessing Administrative Privileges==={|width="40%" align="right" cellpadding="10"|- valign="top"|{{Admon/note|Accessing the Administration Account (root)| Many administrative tasks require the root administrative account. There are many ways to access this administration account:<ul><li>Login: '''root''' (enter root password)</li><li>Switch User to root (without login):<ul><li>'''su''': Remains in regular user's directory, does not run root's startup script(s).</li><li>'''su -''' : Changes to root's home directory (/root) and runs root's start script(s).</li></ul></li></ul>}}|} :'''Perform the following steps:''' #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:1.3em;">su</span></code></b>. This will switch you to the '''root account'''. From there, issue the <b><code><span style="color:#3366CC;font-size:1.3em;">pwd</span></code></b> and <b><code><span style="color:#3366CC;font-size:1.3em;">whoami</span></code></b> commands to confirm your directory pathname. When finished logout of this account using the command <b><code><span style="color:#3366CC;font-size:1.3em;">exit</span></code></b>.#Issue the command <b><code><span style="color:#3366CC;font-size:1.3em;">su -</span></code></b>. Issue the <b><code><span style="color:#3366CC;font-size:1.3em;">pwd</span></code></b> and <b><code><span style="color:#3366CC;font-size:1.3em;">whoami</span></code></b> commands to confirm your directory pathname. What 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></b> has been created to record the installation of your c7host machine. This file is an ASCII file which can be viewed with the <b><code><span style="color:#3366CC;font-size:1.2em;">more</span></code></b> 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 -i packaging /var/log/anaconda/packaging.log | wc -l'''</span></code></b> ===Part 3: Disable SELinux=== {{Admon/important|Never disable SELinux in the real world| It is highly discouraged and unsafe to disable SELinux on a public-facing server. Some applications may require tedious steps to setup SELinux rules. Disabling SELinux is never the correct way to solve an issue.}} 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. :'''Perform the following Steps:''' # Make sure you're logged in as root. <b><code><span style="color:#3366CC;font-size:1.3em;">su -</span></code></b># Edit the file '''/etc/selinux/config''': <b><code><span style="color:#3366CC;font-size:1.3em;">vim /etc/selinux/config</span></code></b># In the editing session, set '''SELINUX''' to '''<u>disabled</u>''' (from ''enforcing'') and save your editing session.# Restart your VM.# You can check the status of SELinux at any time at the command line by typing: <b><code><span style="color:#3366CC;font-size:1.3em;">sestatus</span></code></b> === Part 4: Perform Software Updates=== Running software updates regularly is an important part of keeping your computer secure and stable. On Linux, we use package managers to install software and updates. Package managers not only perform installations, but they keep track of everything that is currently installed on the system for easy management. For CentOS, this manager is called yum. Yum is also the command used.x
:'''Perform the following steps:'''
# Follow the prompts.
# If there is a kernel update, reboot your system. (There usually is on a first update after OS installation.)
'''Answer Investigation 2 observations (all parts and questions) in your lab log book.'''
= INVESTIGATION 3: Using Shell Scripting to Generate System Information Reports =
