Reference no: EM131034803

Assignment:

Can you please put the answer with the question and please use the worksheet

Purpose: To study basic networking commands.

1. Start your machine and log in. Open a command shell.

2. Use the ifconfig command to determine the IP address of your machine:

3. Open the System Settings menu from the side toolbar and select Network. You should see your basic connection described in that window. Click on the Options button (to the right). In the window which appears, you should see several tabs, including one labeled IPv4 Settings. Select that tab and identify the protocol used to obtain an IP address. (This is the "Method".)

4. Close all of those windows so that you can work from the command line. Note that you should read the man page on each of these commands before attempting to use it.

a. Use the who command to get information about people currently logged into the system.

Who do you see?

b. Use the ping command on the address 127.0.0.1, then on the IP address of a popular Internet location (yahoo.com or google.com). Some organizations block these sorts of requests, so try more than one. Use <CTRL>c to stop the pinging.

Password Security

5. Begin the process of adding a new user named generalkala, but have a friend (or significant other or child) assign that new user's password. Tell your friend that the password should be a single, lowercase, alphabetic character.

6. Look at the clock. What time is it?

7. Now open a new command shell and attempt to log into the new account with the su command. You will have to guess the proper password. When you are successful, write down the password and the number of tries you needed to guess it.

Describe your "guessing approach" briefly (Example: "I started at 'z' and worked my way up."):

8. Look at the clock. What time is it?

9. Now use a brief exercise to estimate the strength of these passwords:

a. How long did it take you to find the password (roughly, in seconds)?

b. Divide by the number of attempts to get time per attempt:

c. How many possible passwords did you have to consider?

d. How many possibilities would there be if you had to consider uppercase characters, digits, and other printable symbols from the keyboard?

e. How many possibilities would there be if the password was TWO characters?

f. How many possibilities would there be if the password were allowed to be n characters in length (HINT: You will want an exponent.):

g. Estimate how long it would take to find an 8-character password.Worksheet

Worksheet

Purpose: Access external filesystems, such as the ones on removable storage devices.

NOTE: These instructions reflect the user interface in version 12.04 of Ubuntu, and they assume the student must work through the virtual-machine interface provided by VirtualBox.

1. Boot your system and open two command shells. In one, change your identity to that of the root user.

2. In your root window, move to The Root Directory (NOT root's home directory), then look for the directory named media. Continue to use The Root Directory as your working directory, but look at the contents of the media directory to see if there is anything in it.

3. FOR THE REST OF THIS LAB: Make a point of trying commands in both of your terminal windows. Generally speaking, only the user named root is permitted to manipulate external devices. Try the commands in the window recognizing you under your student identity to test that principle.

4. Compare the output of the df command to the output of the command df . (that is, df "dot")

5. Use less to view the files named fstab and mtab within the /etc directory.

6. Read the man page on mount to see whether you can understand the contents of these files. Then see whether you can find man pages which describe the files themselves. If those pages exist, they will be in section 5 of the manual:
man 5 fstab
man 5 mtab

7. Insert a scratch storage device into an available port - generally speaking, your best choice for this exercise is a small, old USB drive. (NOTE: The following instructions assume the storage device is formatted with a Microsoft filesystem - FAT-32 or NTFS - when the lab begins.)

8. When the device is inserted, the host operating system probably will attempt to mount the device automatically. Bring up your UNIX virtual machine and click on the Devices menu at the top of that window. Then click on the arrow beside USB devices and select the one you have inserted. Doing so will unmount your device from the host operating system and mount it for the virtual machine.
(NOTE: These instructions reflect the VirtualBox 4.01 interface. The specific options may vary with the type of virtual-machine software being used (if any).)

9. The USB drive should have auto-mounted onto your UNIX system, meaning that you should have an icon representing that drive on your desktop. You should also see a directory in the media directory which represents that device - use the ls command to view that directory. Finally, use the df command - do you see the device at the end of that list? What is the device designation of that drive? (It should look something like /dev/sdx.)

10. Use the umount command to unmount that drive. You can do this with a command resembling:
(NOTE: There is no 'n' in umount.)
umount /media/devicename

where devicename should be replaced by the name of your device.
NOTE: If your device name has a space in it - as many devices do, these days - the space may require special handling. Try typing umount /med and then hitting the tab button. The autocomplete feature provided by the UNIX command line should help to handle the white space correctly. How is that accomplished?

11. Create a directory to serve as the mount point for the USB drive within the media directory. Name the new directory: usbdrive.

12. Mount the drive onto your system by hand using a mount command similar to:
mount /dev/sdb /media/usbdrive
NOTE: You should use the device designation you wrote down above RATHER than /dev/sdb.

13. Perform ls -l /media/floppy/ to get a listing of the files on your scratch device. Is there anything you meant to save and did not? If so, stop your experiment and save the files you wish to save. (NOTE the trailing slash. What does that do? Try the same command without the trailing slash - do you get the same result?)

14. Make sure your current working directory is the root directory (or, at least, that you are NOT working in the /media/floppy directory), then unmount the floppy disk again:
umount /dev/sdb
NOTE: You should use the device designation you wrote down above RATHER than /dev/sdb.

15. Read the man page on the mke2fs command; look for information about the manner in which the filesystem is structured. Now use that command to create a UNIX filesystem on your device.
mke2fs /dev/sdb
NOTE: You should use the device designation you wrote down above RATHER than /dev/sdb.

16. Mount the floppy disk onto your filesystem again:
mount /dev/sdb /media/usbdrive
NOTE: You should use the device designation you wrote down above RATHER than /dev/sdb.

17. Repeat step 9 and try to identify any changes you see. An additional step worth performing is to run the mount command with no arguments. From the output of that command, you should be able to learn the specific type of filesystem created on your device (ext2, ext3, or ext4).

Now perform a long listing of the new drive (ls -l /media/usbdrive). You should see a utility directory located at its top level. What is that directory?

Obtain a listing of The Root Directory. Do you see that directory there?

18. Unmount the floppy disk. In the window which recognizes you under your student identity, change to your home directory and create a file named mount.txt. Add your name and the date to that file, then describe how you obtained your scratch device.

19. Copy your file into the directory used for your mount point: /media/usbdrive. Use the more command to read the file (more /media/floppy/mount.txt). (NOTE: The file is not being copied to the device, because you have unmounted the device from your system!)

20. Use your root window to mount the device the way you did before, to the same location. Switch back to your student window and use the more command to read the file - What happened to it?!?

21. In your student window (where you should still be in your home directory), create a new file named whereisit.txt. In that file, describe where you think your mount.txt file has gone.

22. Copy whereisit.txt to the /media/usbdrive directory.

23. Change directories to /media/usbdrive, then use the more command to read the whereisit.txt file located there.

24. Now unmount the USB drive and remove it from your computer.

25. Obtain a listing of the /media/usbdrive directory - what do you see there now?Discussion

Ponder this: Is IPv6 really necessary? Explain your position and be sure to include a real world example in your response. Be sure to include your cited your source(s) to support your position. Read all postings and respond to at least two other postings, following the guidelines for participation. This part of the discussion assignment is due by the end of the academic week to get credit. Again, remember to cite your sources.

Your answer should be well thought out (showing that you have engaged in some critical thinking about the subject matter) and be at the very least, 2 substantial paragraphs in content. Be sure to cite your sources. Failure to do so will result in a zero grade for the assignment.

Assignment: Writing Assignment

Write a short paper (250 to 400 words) reporting on an issue associated with using Linux in a home or small-business environment. This is a formal writing assignment, so make sure your paper exhibits good structure, careful research, and citations for your sources - which must be strong sources.

The first step in writing a good paper is to choose a strong topic. For a short paper like this one, it is important to constrain the topic very narrowly. You may write on a topic of your own choosing, or you may select a topic from this list:
- Describe the differences between hard and soft links.
- Present three situations in which you should consider using the "nice" command.
- Describe the process through which a new user is added to the system.
- Compare a symbolic link located in the Desktop directory of an Ubuntu system with a shortcut located on a Windows desktop.
- Compare some of the features of OpenOffice Calc with Microsoft Excel.

A good place to begin your search for information is the Bellevue University Library - either on-line or in person. Search for articles relevant to your topic. Internet sources are acceptable, as long as they are reputable. Wikipedia and user blogs do NOT qualify as reputable sources, though you are permitted to give credit to them if you used them to help your search. However, your paper must have at least three reputable sources in order to receive credit.

Make sure you provide adequate reference information for every source you use. You must provide a citation for every document that contributes to the paper, even if you do not quote from it directly. Use the APA style guidelines to help format your reference information. For help with citations, you may refer to the following resources:

- American Psychological Association. (2006). APA Style.org.
Retrieved October 26, 2006, from https://www.apastyle.org.
(official site of the style.)

- Russell A. Dewey, PhD. (2006). APA Style Resources.
Retrieved October 26, 2006, from https://www.psywww.com/resource/apacrib.htm. (links to good examples)

- Maimon, Elaine P. and Peritz, Janice H. (2007). Writing Intensive. New York: McGraw-Hill.

Write your paper in a formal style - that is, use the third person whenever possible, do not refer to "this paper", stay away from slang and jargon, and make an effort to remain objective.

One of the most successful ways to structure a paper of this type is to break it down into five paragraphs. The first should be an introduction describing the topic and your research into it. That introduction is followed by three or four paragraphs, each making a single point in support of the paper topic. In each of those paragraphs, use several sentences to provide a clear description of the point you wish to make. Conclude your paper with a paragraph that describes what you have learned. This is a good place to describe your reaction to the material you have read.

When drafting your paper, use a plain-text editor and save it with no formatting of any kind. On Linux systems, use vi or emacs; on MS Windows systems, Notepad is probably your best bet.