ICT246 Tutor-Marked Assignment Questions & Answers – SUSS, Singapore

Question 1 (15 marks)

Choose a Linux operating system (OS) distribution and write 380 words (NOT counting citations) on it.

First, explain the core functions (NOT features) of the Linux OS distribution that you have chosen. Next, describe what this distribution is best suited for. In addition, write a reflection and provides screenshots to describe your experiences with using the Linux OS of your choice. Appropriate citations must be provided.

Note: You are NOT allowed to choose Debian or Ubuntu, and NO marks will be awarded if you choose Debian or Ubuntu. In addition, use your own words and not to copy word for word from the citations provided.

Question 2 (10 marks)

Contrasting the different layers of an OS involves understanding the different layers. Hard disk is an example in the hardware layer that is controlled by the OS. Thus, the ability to compute hard drive metrics is a crucial task.

Determine which of the following 2 hard disks is faster by calculating their respective rotational speeds in rpm.

Disk 1:

The total time to read a file of 800 sectors from disk 1 is 20 ms. The disk has an average seek time of 2 ms, and 300 sectors per track with each sector having 1024 bytes.

Disk 2:

The rotational speed of disk 2 is 168 rps.

Question 3 (30 marks)

Demonstrate the creation and usage of virtual machine using Ubuntu OS.

A small clothing chain NiceBlouse has purchased a server that comes with 7 hard disks (each hard disk has a storage size of 5 TB). The server is pre-installed with Ubuntu OS 24.04, and it has an operational life of 3 years.

The requirements for the storage space are stated as follow:

• 1.5 TB is needed to store transaction records, including customer, order, and delivery details, as well as back-office accounting data. Redundancy is crucial because these are crucial operational data, and even if two hard drives fail at the same time, the data must not be lost.
• A short-term storage area for all employees to quickly share non-essential content, like latest fashion videos. It is projected that this space will require 3.3 TB in the first year, and that amount will increase by 20% (from first year) in the second year and 30% (from second year) in the third year. While performance is crucial, redundancy is not required.
• 2 TB is needed for the marketing department to store different marketing materials, like videos that promote the clothing chain. It is necessary to have redundancy so that no data is lost.
• 1.3 TB is needed for each store (a total of 4 stores) to store materials related to clothing and customer transactions pertaining to that store. Redundancy is required to ensure that no data is lost.

Note that besides the Ubuntu OS, which is pre-installed in a hard disk, you will need to use ZFS to implement the rest of the 6 hard disks. You are NOT allowed to purchase additional hard disks.

Part (a)

Illustrate and justify what RAID system(s) to use for the scenario.

Calculate (with working) and describe how you will organize and use the 6 hard drives. To aid your explanation, sketch a diagram with the appropriate labelling, such as the name(s) of the pool, the file system(s), and the hard drive(s) used (/dev/sdb, /dev/sdc, etc.).

Note: Besides the diagram which is an image, your calculation and explanation must be in editable text so that the Turnitin plagiarism checker can be effective. Marks will be deducted if you do not follow this instruction.

Part (b)

Add six more hard drives into your Ubuntu virtual machine, then use ZFS to simulate the scenario with the appropriate pools and reservations.

Demonstrate with clear explanations and appropriate screenshots.

Note: You can create a scale down storage size for each hard disk such as 5 GB instead of 5 TB if your hypervisor does not allow you to create 5 TB hard disk. You can use Ubuntu Desktop instead of Ubuntu Server for this task.

Question 4 (45 marks)

In this task, you need to implement system security and access control in Linux operating system.

Using Ubuntu OS, write and implement ONE (1) bash shell script (submit only one script for whole Question 4). The script must be executed with no arguments and can be executed in any folder.

The script must have the following specifications:

Part (a)

• The script shall display filenames ONLY for files with an extension of .txt in the current folder. If there is no .txt file in the current folder, the script shall show an error message and terminate.
• It shall display the total number of .txt files in the current folder. If the number of .txt files is greater than 5, it shall display the message “files exceeded 5” and terminate.
• If the number of .txt files is less than 3, it shall display ONLY the following information:
  • filename of each .txt files
  • owner and group of each .txt files
  • first two lines of each .txt files content (note: display the message “first two lines are empty” if the first two lines are empty in the file)
• If the number of .txt files is equal to or more than 3, it shall display ONLY the following information:
  • filename of each .txt files
  • file size of each file
  • total file size of all .txt files

Part (b)

• Next, the script shall display the date stamp of the .txt files in a specific format according to if there is a filename contains a suss. The suss may form part or whole of the filename.
  • If a filename contains suss as part or whole of the filename, display ONLY the filename and date of all .txt files in DDMMYYYY format.
  • If there is NO filename that contains suss as part or whole of the filename, display ONLY the filename and date of all .txt files in DD-MM-YY format.
• It shall invert the execute permission of all .txt files for owner and group ONLY. E.g. if the permission of the .txt file is -rwxr–r–, it shall be changed to -rw-r-xr–.
• It shall then display ONLY the following information for all .txt files:
  • filename of each .txt files
  • permission of each .txt files

Part (c)

A documentation (with appropriate screenshots and explanations) must be produced on the execution of the bash shell script with different conditions to thoroughly test the script, including but not limited to zero .txt files, more than 5 .txt files, .txt file contains suss as part or whole of the filename, zero .txt file contains suss as part or whole of the filename.

Necessary checking must be performed to show the outcomes are correct, including but not limited to checking the permissions of the file has inverted.

Appropriate comments must be added in the script to make it easier to understand.

IMPORTANT:

• Your bash shell script must be in text format within the TMA WORD document. Image of the bash shell script is NOT allowed.
• Embed a notepad file (or WORD file if you are using Mac OS) of the script in the TMA WORD document. Ensure that the embedded file is shown clearly (an example is shown below). Link or URL (e.g. Google Docs) that points to an online source is NOT allowed.
• Note that your script must be able to execute in any folder, and marks will be severely deducted if you hardcode any filepath in your code.

A zero for Question 4 will be given for the following:

• You are not using bash shell script, or your bash shell script cannot be executed in the Azure Ubuntu virtual machine as instructed by the instructor.
• The instructor cannot copy the bash shell script from your TMA WORD document to test. That is, you paste the bash shell script in TMA WORD document as an image, and your embedded script in notepad file (or WORD file) is corrupted.
• You did not include the bash shell script in TMA WORD document, and you only include a link or URL which is not allowed.

50% of the marks will be deducted for the following:

• Your bash shell script does NOT work according to your documentation produced in part (c).
• You did not include part (c).
• You did not include the bash shell script in text format within the TMA WORD document such that the script evades the Turnitin plagiarism checker. That is, you embed a notepad file (or WORD file) but you did not include the bash shell script in text format within the TMA WORD document.