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DRAFT y +1/1/60+ y Student ID (Matricola) 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 Computing Infrastructures Course 095897 P. Cremonesi, M. Gribaudo 25-09-2015 Last Name / Cognome: ................................................................. First Name / Nome: ................................................................. Answers must be given exclusively on the answer sheet (last sheet): DO NOT FILL ANY BOX IN THIS SHEET Students must use pen (black or blue) to mark answers (no pencil). Students are permitted to use a non-programmable calculator. Students are NOT permitted to copy anyone else’s answers, pass notes amongst themselves, or engage in other forms of misconduct at any time during the exam. Students are NOT permitted to use mobile phones and similar connected devices. Scores: correct answers +1 point, unanswered questions 0 points, wrong answers -0.333 points. Reserve questions must NOT be answered, unless explicitly stated during the exam. y For your examination, preferably print documents compiled from auto-multiple-choice. y DRAFT y +1/2/59+ y Disks Consider the following set of disks connected in RAID 6, with generatorg = 2: !" # !$ % !# $ !% $ & ' ( #" !" ) !$ % !# $ & $# ( $) !% " !" " !$ " & $ ( ) !# " !% $ *+,-./01 *+,-./0$ *+,-./0# *+,-./0% *+,-./02 *+,-./03 *+,-./41 *+,-./*$ *+,-./*# *+,-./*% *+,-./*2 *+,-./*3 *+,-./*1 *+,-./4$ *+,-./4# *+,-./4% *+,-./42 *+,-./43 Figure 1: A RAID 6 configuration. Question 1 What data is contained in blocksA3 and A6? A D2 = 13, Q = 68 B D2 = 1, Q = 20 C D2 = 0, Q = 18 D Cannot be com- puted SOLUTION: D2 = 1, Q = 20 Question 2 Data in blockC2 is changed toD1 = 3. Which are the new values of the parity blocks? A P = 4, Q = 14 B P =…