Reference no: EM131004374

Purpose: To practice UNIX command-line syntax.

NOTE: These instructions reflect the user interface installed with Ubuntu 12.04 LTS.

1. Boot your Ubuntu system and open a command shell (Dash Home at the top left; type "term" in the search box to find the application). What is your command prompt?

2. Issue the ls command, then the ls -l command. (NOTE: There is a space there.) What is the meaning of the -l option? Issue the command man ls to read the manual and verify your answer.

3. Repeat the second command you typed above, but this time leave the space out. What command did the shell attempt to execute?

4. Read the manual page on the ls command again. How many parameters are required?

5. Now have a look at the manual page for the adduser command. This command is more complicated than the ls command, because it can be used in several forms. Fortunately the first is the most common; look at those lines of text and identify any required parameters.

6. Execute the command man -k directory. What command will allow you to print the name of your current working directory?

7. Use the up arrow to bring up the previous command. Backspace to delete the word "directory", then type the word "users" to get a list of commands associated with that topic. Which command would you use to get a list of users currently logged into the system?

How about to get a list of "last logged in users" (choose one of the two)?

8. Execute the command which ls and record the result:

9. Read the manual page on the which command and describe what the command is doing.

Purpose: This worksheet guides you through the process of setting up an Ubuntu Linux virtual machine using VirtualBox from Oracle.

NOTE: There are many ways to set up a UNIX environment, including the use of dual-boot systems and dedicated systems. For most students, the most convenient approach is likely to be that of creating a virtual machine. The following instructions describe the creation of a virtual machine using:
Windows 7 (host operating system)
VirtualBox 4.2.8 (VirtualBox-4.2.8-83876-Win.exe)
Ubuntu 12.04 LTS (ubuntu-12.04.2-desktop-i386.iso)

Downloading Software

Since the Internet is a rapidly-changing environment, it is difficult to ensure that web sites will always be available at the same locations. For the software described above, students should start with:
www.virtualbox.org
www.ubuntu.com
and with the Bellevue University MSDNAA relationship (which facilitates the download of Microsoft software).

Installing VirtualBox

1. Start the VirtualBox installation by double-clicking on the file you downloaded.

2. Choose Run, then Next, from the screens which appear. When you reach the Custom Setup screen, select Next for the default installation.

3. Choose where you wish icons to appear.

4. You will receive some warnings about network drivers and about how the installation process may disconnect you from the network for a while. What is happening here is that VirtualBox is setting up hardware interfaces which may be used by the virtual machines it is going to manage - those generic interfaces allow your system hardware to be used by virtual machines of any type. However, in order to get those generic interfaces installed, the VirtualBox installation must temporarily disable the existing ones. Click Yes then Install to accept this condition and proceed with the installation. Continue to choose Install when prompted about the installation of driver software.

Setting up a Virtual Machine With VirtualBox

1. Start the PC and log in to a user identity with administrative control over the machine. Start the VirtualBox application.

2. Within the VirtualBox control window, you will see an inventory menu (on the left) and a main window. Above the inventory list is a group of action buttons; choose New to start the wizard which will help you create a new virtual machine.
NOTE: Before starting this process, check to make sure there is enough disk space available on your machine. Also, check the inventory of virtual machines to see what is already in place.

3. Enter the name Ubuntu12.04 into the name space.

4. Select Linux as the operating system in the OS box, then use the drop-down Version box to identify the OS as an Ubuntu system (Use Ubuntu 64-bit only if you have hardware for that and downloaded the appropriate version). Click NEXT.

5. Allocate memory to your virtual machine. VirtualBox will recommend 512 MB - this may be sufficient, but unless the RAM on your machine is very limited, you may wish to choose at least 1GB. Remember that allocating more memory to the VM will reduce the amount of memory available to the host operating system when the VM is running (but not otherwise). Click NEXT.

6. Create a virtual hard drive for this virtual machine (that is, make sure the create a new virtual hard drive button is checked), and indicate that it should use a new disk. Click CREATE.

7. Within the disk-creation wizard, choose the type of file you wish to use. If your virtual machine will be used exclusively with VirtualBox, choose the VirtualBox Disk Image. Click NEXT. Specify that the disk should use dynamically-expanding storage. Click NEXT.

8. Accept the defaults for the location where the disk will be stored (which should be Ubuntu12.04) and size (which should be 8 GB). Click NEXT.

9. Click CREATE to close the disk-creation wizard, then click CREATE again to close the virtual-machine creation wizard.

Installing Ubuntu

1. Start your Ubuntu12.04 virtual machine and read the notice which appears. It provides you with information which will help you to understand where your keyboard and mouse input is going at any given time. Read this, understand it, take notes if you believe it will help.

2. Read the First Run Wizard splash page and click NEXT.

3. Select the installation medium on which your UNIX operating system has been stored. If you burned a CD, select the appropriate drive. Alternatively, you may install from an image which is stored on the hard drive of your host computer. To do this:
Click the folder with the green chevron on the right side of the window.
In the window which appears, navigate to the ISO image you downloaded.
(NOTE that the dialog window may not behave exactly the same way that a Windows Explorer window does.)
Verify that the image is specified in the entry box.
Click NEXT.

4. You will see some notifications - possibilities include color resolution and mouse capture notices. Read these for informational purposes and move on.

5. When the Welcome window appears in your virtual machine, verify that English is selected and click on the Install Ubuntu button to the right.

6. Your virtual machine should meet the requirements described in the preparation window. Check the Download Updates box, but do not check the third-party software box. Click FORWARD.

7. Verify that Erase and Use Entire Disk is selected, then click FORWARD or CONTINUE.

8. Leave the defaults on the Allocate Disk Space window and click Install Now.

9. Choose the correct time zone. Click FORWARD.

10. Choose an appropriate keyboard layout (probably USA). Click FORWARD.

11. Enter names for yourself and your machine. For classroom purposes, set the password to r3pL8s. Click FORWARD.

12. Wait for the system to install. You will be asked to restart the computer (meaning the virtual machine, not your host machine). Do so. NOTE: Some Ubuntu OSes hang at the moment you are instructed to "remove CD/DVDs and close the tray". If you click Machine, at the top left, then choose Close and Power Down, the virtual machine will close.

13. If your VM is not restarting on its own, re-start it once again. NOTE: If you used a virtual CD/DVD drive to install, the VM may attempt to boot from it again. Press F12 as the VM starts, and you will be able to instruct the VM to boot from your newly-created virtual hard disk.

14. Recent releases of VirtualBox and Ubuntu have begun to exhibit a strange behavior. That is, the Ubuntu installation does not recognize the VirtualBox video drivers (this is worth discussing on the board), forcing the system to boot into "low graphics mode". This may strike you as strange, since the installation process had no difficulty using graphics . . . it seems counter-intuitive that the graphics support would get WORSE. However, you will want to take steps to restore graphics support. To do this, we will have to install the "guest additions" from INSIDE the new virtual machine.

NOTE: If you do not see anything about "low graphics mode", you can skip ahead to #22 and count yourself lucky.

15. Click through the screens, accepting the low graphics mode for one session, to reach a basic command prompt. Note that the visibility of the mouse pointer is likely to be spotty, so you might have to watch for shading changes in the acceptance boxes as you work your way to the command prompt.

16. Enter the username and password you created during the installation process.

17. In order to install the Guest Additions, we must set up the virtual machine so that it can make changes to the operating system (this also is worth discussing on the board). At the command prompt, type:
sudo apt-get install dkms
This will install a set of packages which allow the re-compilation of the kernel. NOTE: You will have to enter your own password in order to get the command to run, since it must be run as an administrative user. (This also is worth discussing on the board.) Type y for yes when prompted.

18. Next we must mount the CD-ROM (a virtual one) which contains the Guest Additions. Click on Devices, then hover over CD/DVD Devices. If the VBoxGuestAdditions.iso entry appears on your list, choose it. If it does not, you will have to navigate to that file. Click the folder icon with the green chevron at the top of the list, then navigate to the folder containing it - that should be something similar to C:\Program Files\Oracle\VirtualBox. This simulates the opening of the CD tray, the placement of the disc, and the closing of the tray.

19. At the command prompt, type:
sudo mount /dev/cdrom /cdrom
This tells the operating system to give you access to the files on the CD, and to make those files available in the location named /cdrom.
NOTE: This sort of thing is done automatically by most GUI OSes.

20. At the command prompt, type:
sudo sh /cdrom/VBoxLinuxAdditions.run
This will configure the operating system with the additional drivers required to make use of the VirtualBox facilities.

21. Restart the virtual machine. You can do this either through the VM menu entries or by typing
sudo shutdown -r now

22. Log on to the system with the username and password you created before.

23. Study the screen. Notice the similarities and differences between what you see there and the Windows interface you (most likely) find more familiar. Click on Applications, then Accessories, then Terminal. At the command prompt, type ls and hit Enter. Look at the results. Type pwd at the command prompt, then hit Enter. Again, look at the results.

24. Though almost all versions of Linux offer GUI interfaces, we will do a lot of work from a command line - like the one you have open now, and like the prompt you used to get your graphics working. By default, Ubuntu does not permit anyone to log into the system as the user named root. However, CIS 240 requires that a lot of work be done under that identity. Therefore, you should assign a password to root, so that you can log into that account directly. In the terminal window, run the command:
sudo passwd root
Enter the same password you used for your personal account.

16. IMPORTANT: You should always shut down your operating system before turning the (virtual) machine off. Click the "power" icon at the top right of your virtual-machine window (the circle with a line at the top). Select Shut Down and follow the instructions which appear.

This week, both of the labs are "worksheets", meaning that they will not be graded - and even one of those is optional, because it involves gaining access to a UNIX system. For most students, the best way to accomplish this is by installing Linux into a virtual machine. This process is described in Worksheet #0, attached here, for an Ubuntu Linux system installed into a VMWare virtual machine. Note, however, that students who have access to UNIX systems through other facilities are free to make use of them rather than going through Worksheet #0.

Why are virtual machines recommended for this course? What is happening, currently, in the world of VM servers? Remember to cite your sources.

Attachment:- Unix Class.rar