Question

1. What are the 5 major components of a hard disk drive (10pts)? Describe the basic function of each component (10pts).

2. Give two examples of memory that are commonly used for large scale and permanent data storage in system administration (4pts). What are the three commonly used storage access methods in system administration (6pts)?

3. Assuming there are 35 SSDs, how many different types of RAID 50 can be built using all 35 SSD? Draw the layout of each RAID 50 (10pts). For each RAID 50 built, what is the maximum utilization of the disks? Show the process of calculation and then the final result for each one (10pts).

4. What is a block device used for (4pts) in the operating system? Give three instances of block devices for the memory (6pts).

5. Give two examples of filesystems that are commonly used in windows OS (4pts) and three examples of filesystems that are commonly used in Linux OS (6pts).

6. In ext4, what are the 5 BASIC types of block (10pts). Describe the basic function for each type of block (10pts).

7. List five basic operations in system administration (10pts).

Answer 1

1.

i.) .Disk Platters - A platter is considered the physical medium where data is stored in a disc drive, and the disc platters are stiff, thin circles that rotate under the drive spindle motor 's control. The three elements are the substrate, the magnetic layer and the protective overcoat layer.

ii.)Read and Write Heads - Reading and writing heads are the processing heads used to transfer data to and from the platter. It is the duty of reading / writing heads to record and play back data stored on the magnetic layer of disc platters. They cause magnetic signals to be imprinted on the magnetic molecules in the media as they write, and sense the effect of those signals while they read.

iii.)Read/Write Channel - Although in the digital world we prefer to think of data exclusively, the actual documentation is an analogue signal. Somehow, it is important to transform the 0s and Iss of digital logic to anything that allows a magnetic media impact. In other words, disc data does not at all imitate written text, but is represented by a magnetic signal pattern on moving discs. The read / write channel is the subassembly of the disc drive that offers a specialised digital / analogue conversion.

iv.)Arms and Actuators - It is important to locate the reading and writing heads correctly over unique channels. They are attached to disc arms as very small arc heads, which are thin, stiff, triangular parts of lightweight alloys. The disc arms are produced with microscopic accuracy, like anything else within a disc drive, so that the read / write heads can be easily and correctly placed precisely next to the platters.

v)Drive Spindle Motor and Servo Control Electronics - The drive plates rotate under the control of the motor of the drive spindle, which is engineered to sustain steady speeds for long stretches of time with minimum friction, often measured in tens of thousands of hours.