Q1.Main categories of hard disk drive failure?
According to Elerath there are basically two types of hard disc failures, the first one which is also referred to as operational normally prevents access to the data stored on the hard disc while the second type which do not in any case affect the hard disk but rather corrupts the stored data. In the second category the problem can be identified only when data is read and is found to be corrupt, these are called latent defects. Operational failures are results of bad tracks, dysfunctional electronics, and head failure to stay on track, defective read head and exceeding SMART limit. On the other to case of latent failures the cause is a connected error while writing data which may result from spoilt media, bit errors or speedy writing, poling of normally written data due to thermal asperities, corrosion or scratched media (Elerath, 2009).
How SMART technology work
The SMART technology is normally inbuilt in hard disks and allows the user to keep track of hard disk performance and impending failures. It works by constantly tracking condition of a variety of parameters in the hard disk. In many cases there is sector relocation on hard disks. This is normal but if at a given interval an excessive reallocation occurs the hard disk will be unreliable and this is known as exceeding SMART limits (Elerath, 2009).
2. Based on Thibodeaus (2008) article, what are the advantages and disadvantages of the use of mainframes?
The major advantage of mainframe is their reliability. This is demonstrated by their ability to work for long time without crashing or having system failures. This is a big problem which can lead to huge data losses. Another advantage is space efficiency as compared to servers which are small but a greater number is required in an organization (Thibodeau, 2008). It also offers consolidation of workload. Another benefit is cost which is demonstrated as cheap as compared to other systems.
The drawbacks of mainframes include the following, assumed hard to use and operate this is coupled with incompatibility of applications employed in the mainframes. The necessity of improvement indicates some problems (Thibodeau, 2008). Another problem is vulnerability and the high cost initial cost of acquiring these large machines.
References
Thibodeau, Patrick. (2008). Mainframes Fight to Keep Corporate IT Crown Computerworld; Feb 18, 2008; 42, 8; ProQuestpg. 12
Jon Elerath. (2009). Hard-Disk Drives: The Good, the Bad, and the Ugly 38 communications of the acm. june 2009, vol. 52 no. 6
