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I hope youve liked all the writing involved in the last hour, because the method of troubleshooting in this hour involves a great deal more of it. Treating a complex problem usually involves a lot of note-taking, because you have to fill in the gaps where your understanding of the problem is incomplete. Up until now, youve treated problems the way you treat a multiple-choice testwith change analysis, divisive reasoning, and matching. Now, were talking about a fill-in-the-blank test, and it gets a little bit harder; this is the hour where you have to wade through the subjective, match it up with the objective, analyze your data, and plan on what to do next. In other words, this is the hour you want to save for the tough problems.
First, a little bit about the SOAP method. I first encountered the SOAP method while I was deciding not to be a doctor like my father. Although I had absolutely no interest in sticking needles into people, hanging around my father in his office taught me a lot about troubleshooting. In a sense, medicine is much harder than computingthere are hardly any standards, the designer never released the data sheets (much less the full documentation), and the device youre trying to troubleshoot can sue you if you make a mistake. The medical profession has come up with all sorts of diagnostic trickswe as network troubleshooters have a great deal to learn from the medical profession.
One of those diagnostic techniques is the SOAP method of note-taking. On their patients charts, some doctors write down on separate lines the letters S, O, A, and P, standing for Subjective, Objective, Analysis, and Plan, respectively. Therefore, if I went to see the doctor about my stomach, he might write:
The subjective is what I say to the doctor, the objective is what the doctor sees, the analysis is what he deduces from his additional questions and reasoning, and the plan is what he will do to try to treat the problem, plus the next step. Doctors are used to not being able to get a black-and-white answer; however, if they have a plan, they are going in the right direction.
Going in the right direction is what the SOAP method is all about. Not every problem you run into as a troubleshooter is going to be solvable within that day or weekparticularly problems that are not show-stoppers (emergency room visits). In particular, problems that come and go (intermittent problems) are usually long-term and complex troubleshooting jobs. To be able to wrap your arms around a complex problem, you have to segregate the problem into its component partsthat is, the subjective report and the objective facts. Its particularly important to be able to separate the subjective outsomeone may be reporting something that has some bearing on the problem but perhaps is not pointing directly at the problem. Consider someone whos reporting chest painsis this person reporting a heart attack or a muscle problem? The report of pain in the chest is a subjective feelingthe active investigation that reveals a heart attack or muscle pain is the objective finding. The subjective is useful but can only be borne out by investigation.
When considering the facts in an intermittent or complex network issue (also known in the industry lingo as troubleshooting a weird problem), you need to categorize a basic list of objective items that can help point towards a solution:
Even though you may have a lot of objective data, you might not have the right objective data to analyze in order to come to the right conclusion. Therefore, your plan item on your first couple of tries on a tough problem will probably be to gather more data. Dont give up; the more data you have, the better guess you can make.
Lets take a case in which a user says she cant run a particular Web applet that she needs for her job. Figure 6.1 shows a logical map of the site; her PC lives at point A on the map.
Figure 6.1 Troubleshooting a time-related problem.
You visit the users PC and can run the applet just fine. She frowns at you, and says, Well, it doesnt work for me. She tries right after you, and it works, but she reports the problem again the next day. You decide to use SOAP on this one:
Your analysis of the problem is a good one, and your plan to gather new information works. You visit her when she usually tries her Web applet, and, sure enough, it wont work for you. Whats going on? This time through, youre the one supplying the subjective data; its your guess:
An okay plan, but it doesnt work out, as shown from your notes:
She still has problems at 8:00 a.m. on a different network segment. Thats fine. Youve now ruled out her network segment, and thats very important to do. Youve made a deduction, and its wrong. Dont sweat it.
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