1 00:00:00,090 --> 00:00:01,830 In this lesson, we're going to talk about 2 00:00:01,830 --> 00:00:04,350 step three of the troubleshooting methodology, 3 00:00:04,350 --> 00:00:06,090 which is test the theory. 4 00:00:06,090 --> 00:00:07,530 Now, CompTIA writes this down 5 00:00:07,530 --> 00:00:10,080 as test the theory to determine the cause. 6 00:00:10,080 --> 00:00:11,610 Once that theory is confirmed, 7 00:00:11,610 --> 00:00:14,280 determine the next steps to resolve the problem. 8 00:00:14,280 --> 00:00:15,750 If the theory is not confirmed, 9 00:00:15,750 --> 00:00:18,570 reestablish a new theory or escalate, 10 00:00:18,570 --> 00:00:21,150 and this is what we're focused on in step three. 11 00:00:21,150 --> 00:00:23,820 So in step one, we identified our problem. 12 00:00:23,820 --> 00:00:25,380 In step two, we came up with an idea 13 00:00:25,380 --> 00:00:28,200 of what we thought the probable cause of that problem was, 14 00:00:28,200 --> 00:00:29,460 and now here in step three, 15 00:00:29,460 --> 00:00:32,910 we're going to test our theory to see if we were right. 16 00:00:32,910 --> 00:00:34,440 Now, up to this point, we have done 17 00:00:34,440 --> 00:00:36,930 a lot of work in thinking about the problem, 18 00:00:36,930 --> 00:00:39,180 but we haven't done any kind of configurations 19 00:00:39,180 --> 00:00:42,450 or changes to the system to try to solve that problem. 20 00:00:42,450 --> 00:00:43,950 And now that we're here in step three, 21 00:00:43,950 --> 00:00:45,570 we can finally do that. 22 00:00:45,570 --> 00:00:48,210 So let's say for example, we had a system 23 00:00:48,210 --> 00:00:50,730 that wouldn't turn on, well, if we have a system 24 00:00:50,730 --> 00:00:53,370 that won't turn on, it can be lots of different problems, 25 00:00:53,370 --> 00:00:55,800 but we thought the problem was this computer 26 00:00:55,800 --> 00:00:57,630 wasn't plugged into the wall outlet. 27 00:00:57,630 --> 00:00:59,610 Now it's a really simple theory to test. 28 00:00:59,610 --> 00:01:02,400 We can simply trace the cable from the back of the tower 29 00:01:02,400 --> 00:01:04,560 into the wall outlet and see if it's plugged in, 30 00:01:04,560 --> 00:01:07,290 and if it's not, that tells me that was the problem. 31 00:01:07,290 --> 00:01:09,060 Let's plug it in, turn on the computer 32 00:01:09,060 --> 00:01:12,060 and see if it boots up, if it does, that was the problem, 33 00:01:12,060 --> 00:01:13,110 we have now confirmed it, 34 00:01:13,110 --> 00:01:15,630 and our theory has solved the problem. 35 00:01:15,630 --> 00:01:17,550 But let's say we got there and the cable 36 00:01:17,550 --> 00:01:19,020 wasn't plugged into the wall. 37 00:01:19,020 --> 00:01:20,550 We plugged the cable into the wall, 38 00:01:20,550 --> 00:01:23,700 we pushed the power button, and nothing happens. 39 00:01:23,700 --> 00:01:25,470 The computer still won't turn on. 40 00:01:25,470 --> 00:01:28,080 Well, now our theory of it being unplugged 41 00:01:28,080 --> 00:01:30,480 being the root cause is no longer valid, 42 00:01:30,480 --> 00:01:33,540 so we need to now create a new theory. 43 00:01:33,540 --> 00:01:35,340 Based on the different symptoms we had, 44 00:01:35,340 --> 00:01:36,660 based on what we've observed, 45 00:01:36,660 --> 00:01:38,130 and based on what we've done so far, 46 00:01:38,130 --> 00:01:40,140 we know that what we thought was the problem 47 00:01:40,140 --> 00:01:42,810 is no longer the problem, and so we need to figure out 48 00:01:42,810 --> 00:01:45,510 what is the next theory or probable cause 49 00:01:45,510 --> 00:01:46,890 that we're going to attempt. 50 00:01:46,890 --> 00:01:48,960 In this case, I might say the wall outlet 51 00:01:48,960 --> 00:01:51,870 doesn't provide enough power, so I make a theory 52 00:01:51,870 --> 00:01:53,790 that the wall outlet is the problem. 53 00:01:53,790 --> 00:01:56,490 So I step back to step two, I create a new theory 54 00:01:56,490 --> 00:01:59,040 and I say, I think the wall outlet is the problem. 55 00:01:59,040 --> 00:02:01,860 Now I'm back in step three, I need to test that theory. 56 00:02:01,860 --> 00:02:04,770 So I grab my volt meter, I plug it into the wall, 57 00:02:04,770 --> 00:02:07,920 and I test and I see that I'm getting 120 volts AC, 58 00:02:07,920 --> 00:02:09,720 and since I'm located here in the United States, 59 00:02:09,720 --> 00:02:12,390 that's perfectly fine, so that's not my problem. 60 00:02:12,390 --> 00:02:15,660 So I need to establish another theory and try again. 61 00:02:15,660 --> 00:02:17,700 So maybe I think it's the power supply 62 00:02:17,700 --> 00:02:19,200 itself that's the problem. 63 00:02:19,200 --> 00:02:21,570 And now I can use that as my new theory 64 00:02:21,570 --> 00:02:23,820 and start working towards that to confirm it. 65 00:02:23,820 --> 00:02:26,070 The idea here is we guess on something, 66 00:02:26,070 --> 00:02:29,130 we then try to test that theory, and if we test that theory 67 00:02:29,130 --> 00:02:30,900 and find it's not the cause, 68 00:02:30,900 --> 00:02:33,300 we are then going to have to get a new theory. 69 00:02:33,300 --> 00:02:36,090 If we did test the theory and we confirm that theory, 70 00:02:36,090 --> 00:02:37,680 the next steps are going to be to resolve 71 00:02:37,680 --> 00:02:39,690 the problem for the long term. 72 00:02:39,690 --> 00:02:42,210 So at this point, if we tested the power supply 73 00:02:42,210 --> 00:02:43,650 and found that it was faulty, 74 00:02:43,650 --> 00:02:45,900 we would have now confirmed our theory, 75 00:02:45,900 --> 00:02:48,090 and at this point, we would then need to determine 76 00:02:48,090 --> 00:02:50,970 the next steps that we have to resolve this problem. 77 00:02:50,970 --> 00:02:52,710 That could be fixing the power supply, 78 00:02:52,710 --> 00:02:54,030 replacing the power supply, 79 00:02:54,030 --> 00:02:56,610 or maybe even replacing the entire computer 80 00:02:56,610 --> 00:02:58,290 depending on how old that unit is 81 00:02:58,290 --> 00:03:00,600 and what your corporate policies are. 82 00:03:00,600 --> 00:03:02,640 Another thing to keep in mind here in step three 83 00:03:02,640 --> 00:03:04,980 when you're testing the theory to determine the cause, 84 00:03:04,980 --> 00:03:07,500 is that you really have four possible outcomes. 85 00:03:07,500 --> 00:03:09,870 The first is that your theory is confirmed, 86 00:03:09,870 --> 00:03:12,540 and in this case, you're going to take steps to fix it. 87 00:03:12,540 --> 00:03:15,060 The second is your theory is not confirmed, 88 00:03:15,060 --> 00:03:16,740 and you need to come up with a new theory 89 00:03:16,740 --> 00:03:18,300 and then try to test that theory, 90 00:03:18,300 --> 00:03:20,700 and if you find it, then you're going to fix it. 91 00:03:20,700 --> 00:03:23,250 The third is you identified the problem, 92 00:03:23,250 --> 00:03:24,270 you've tested your theory 93 00:03:24,270 --> 00:03:25,920 and you figured out what the problem is, 94 00:03:25,920 --> 00:03:27,720 but you don't have the skills 95 00:03:27,720 --> 00:03:30,330 or the authority to fix that thing. 96 00:03:30,330 --> 00:03:32,370 For example, maybe you've identified 97 00:03:32,370 --> 00:03:35,820 that this particular fix is going to require a $10,000 part, 98 00:03:35,820 --> 00:03:37,080 and you're not authorized to replace 99 00:03:37,080 --> 00:03:38,940 that part in that system. 100 00:03:38,940 --> 00:03:41,310 Well, in this case, you'd have to escalate that up 101 00:03:41,310 --> 00:03:43,440 to the team that's responsible for that server 102 00:03:43,440 --> 00:03:45,630 or that piece of equipment, so they can then replace 103 00:03:45,630 --> 00:03:48,720 that part or they get the approval to replace that part. 104 00:03:48,720 --> 00:03:50,550 Another side of this might be you don't have 105 00:03:50,550 --> 00:03:52,560 the skills to fix that thing yet. 106 00:03:52,560 --> 00:03:53,880 Maybe you found there was an issue 107 00:03:53,880 --> 00:03:55,890 that was happening across multiple systems 108 00:03:55,890 --> 00:03:57,990 that you're supporting, and when you look at it, 109 00:03:57,990 --> 00:04:00,840 you figured out that the issue had to do with a group policy 110 00:04:00,840 --> 00:04:02,910 that was being pushed out from the Windows server. 111 00:04:02,910 --> 00:04:05,040 But you don't work in the Windows server group, 112 00:04:05,040 --> 00:04:07,200 so you're going to have to escalate this issue 113 00:04:07,200 --> 00:04:08,880 over to the Windows server group 114 00:04:08,880 --> 00:04:10,710 so that that team can change the policies 115 00:04:10,710 --> 00:04:12,480 and configurations that they're pushing out 116 00:04:12,480 --> 00:04:14,250 to all the systems across the domain 117 00:04:14,250 --> 00:04:16,560 and fix this larger problem. 118 00:04:16,560 --> 00:04:18,779 Another issue might be where you have to escalate this 119 00:04:18,779 --> 00:04:20,940 and bring in some outside support. 120 00:04:20,940 --> 00:04:22,890 Maybe you found out that the reason this system 121 00:04:22,890 --> 00:04:25,290 isn't working right is that it was infected by malware 122 00:04:25,290 --> 00:04:27,030 or there's an attacker in your system 123 00:04:27,030 --> 00:04:28,980 and they have control of that system. 124 00:04:28,980 --> 00:04:30,690 In that case, as a technician, 125 00:04:30,690 --> 00:04:32,640 we are probably not going to be the ones to fix that, 126 00:04:32,640 --> 00:04:35,310 but instead, we're going to call in the cybersecurity experts 127 00:04:35,310 --> 00:04:37,200 who are going to come in and kick those bad folks 128 00:04:37,200 --> 00:04:39,240 out of our network and off of that box 129 00:04:39,240 --> 00:04:41,760 so that we can gain access to it once more. 130 00:04:41,760 --> 00:04:44,610 Again, a lot of this is going to depend on your organization, 131 00:04:44,610 --> 00:04:47,340 the policies, procedures, and authorities that they give 132 00:04:47,340 --> 00:04:49,110 to the technicians at different levels. 133 00:04:49,110 --> 00:04:51,420 But keep in mind that one of the things you could do 134 00:04:51,420 --> 00:04:54,390 is escalate this when there's an issue. 135 00:04:54,390 --> 00:04:55,980 Now, the fourth possible outcome 136 00:04:55,980 --> 00:04:57,720 is that you tested your theory, 137 00:04:57,720 --> 00:05:00,360 you come up with a bunch of theories, and you're just stuck. 138 00:05:00,360 --> 00:05:01,590 You don't know what the right answer is, 139 00:05:01,590 --> 00:05:03,450 you don't know how to fix this problem. 140 00:05:03,450 --> 00:05:05,010 And in those cases, you would again, 141 00:05:05,010 --> 00:05:07,440 need to escalate this to the next higher level. 142 00:05:07,440 --> 00:05:10,800 In most organizations, we have a tiered support structure 143 00:05:10,800 --> 00:05:14,250 of tier one, tier two, and tier three support technicians. 144 00:05:14,250 --> 00:05:17,250 Tier one is going to solve all of the most basic problems. 145 00:05:17,250 --> 00:05:18,720 Over time, you're going to gain more skills 146 00:05:18,720 --> 00:05:19,800 and you'll move up to tier two 147 00:05:19,800 --> 00:05:21,720 where you can solve some more advanced problems. 148 00:05:21,720 --> 00:05:23,550 And we get to tier three, that's really where you start 149 00:05:23,550 --> 00:05:25,350 dealing with the subject matter experts, 150 00:05:25,350 --> 00:05:27,240 people who are the system administrators, 151 00:05:27,240 --> 00:05:29,520 the server administrators, the cryptographic 152 00:05:29,520 --> 00:05:32,160 and cybersecurity experts, and things like that. 153 00:05:32,160 --> 00:05:34,620 Now, over time, you may move into those positions, 154 00:05:34,620 --> 00:05:36,360 but today, when you're first starting out, 155 00:05:36,360 --> 00:05:39,300 you're probably going to be in tier one or maybe tier two, 156 00:05:39,300 --> 00:05:40,380 and so there are going to be some things 157 00:05:40,380 --> 00:05:42,990 that you just don't know how to identify or how to fix, 158 00:05:42,990 --> 00:05:44,790 and in those cases, you're going to want to escalate 159 00:05:44,790 --> 00:05:46,350 those tickets up to tier two 160 00:05:46,350 --> 00:05:48,510 or tier three for additional assistance 161 00:05:48,510 --> 00:05:50,860 so they can solve the problem for the end user.