Trobleshooting Methodology

The Article below was taken from this website.

Troubleshooting Methodology

Troubleshooting generally consists of the following steps. Different methodologies may call them by slightly different names, but the similarities are pretty obvious.

• Investigation
  • Problem Statement: Create a clear, concise statement of the problem.
  • Problem Description: Identify the symptoms. What works? What doesn’t?
  • Identify Differences and Changes: What has changed recently? What is unique about this system?
• Analysis
  • Brainstorm: Gather Hypotheses: What might have caused the problem?
  • Identify Likely Causes: Which hypotheses are most likely?
  • Test Possible Causes: Schedule the testing for the most likely hypotheses. Perform any non-disruptive testing immediately.
• Implementation
  • Implement the Fix: Complete the repair.
  • Verify the Fix: Is the problem really fixed?
  • Document the Resolution: What did we do? Get a sign-off from the system owner.

Problem Statement

The problem statement must be broad enough to describe the problem, but narrow enough to focus the investigation. It should not contain value judgements. It should be a factual answer to the question “What is wrong?”

Problem Description

Gather all symptoms, including error messages, core dumps, descriptions of any service outages, and contrasting descriptions of what still works. As near as possible, we need to identify the time of the incident.

Identify Differences and Changes

Identify differences between the faulted system and any similar working systems. Also identify any recent changes to the system.

Brainstorm

In this stage, we need to come up with as many possible explanations for the problem as possible. It is sometimes helpful (especially in a group setting) to use an Ishikawa diagram to organize our thoughts so that we don’t leave any possibilities unconsidered.

Generate an Ishikawa diagram by drawing a “backbone” arrow pointing to the right at the problem statement. Then attach 4-6 “ribs,” each of which represents a major broad category of items which may contribute to the problem. Each of our components should fit on one or another of these ribs.

Identify Likely Causes

We need to consider how likely each potential cause is. We should only eliminate hypotheses when they are absolutely disproven.

For more complex problems, something like an Interrelationship Diagram may be useful in identifying which potential cause may be might be a root cause.

Interrelationship Diagrams use boxes containing phrases describing the potential causes. Arrows between the potential causes demonstrate influence relationships between these issues. Each relationship can only have an arrow pointing in one direction. (Where the relationship’s influence runs in both directions, the troubleshooters must decide which one is predominant.) Items with more “out” arrows than “in” arrows are causes. Items with more “in” arrows are effects.

Test Possible Causes

We need to perform testing in the least disruptive fashion possible. Data should be backed up if possible before testing proceeds.

The best approach is to schedule testing of the most likely hypotheses immediately. Then start to perform any non-disruptive or minimally disruptive testing of hypotheses. If several of the most likely hypotheses can be tested non-disruptively, so much the better. Start with them.

In some cases, it may be possible to test the hypothesis directly in some sort of test environment. This may be as simple as running an alternative copy of a program without overwriting the original. Or it may be as complex as setting up a near copy of the faulted system in a test lab. If a realistic test can be carried out without too great a cost in terms of money or time, it can really help nail down whether we have identified the root cause of the problem.

Depending on the situation, it may even be appropriate to test out the hypotheses by directly applying the fix associated with that problem. If this approach is used, it is important to only perform one test at a time, and back out the results of each failed hypotheses before trying the next one. Otherwise, you will not have a good handle on the root cause of the problem, and you may never be confident that it will not re-emerge at the worst possible moment.

Implement the Fix

The fix needs to be implemented in the least-disruptive, lowest-cost manner possible. Ideally, the fix should be performed in a way that will completely verify that the fix itself has resolved the problem.

Verify the Fix

We need to check that the problem is resolved, and also that we have not introduced any new problems. Each service in your environment should have a test suite associated with it so that you can quickly eliminate the possibility that we have introduced a new problem.

Part of this verification should include a root-cause analysis to make sure that the real problem has been resolved. Band-Aid solutions are not really solutions.

Document the Fix

Over time, the collection of data on resolved problems can become a valuable resource. It can be referenced to deal with similar problems. It can be used to track recurring problems over time, which can help with a root cause analysis. Or it can be used to continue the troubleshooting process if it turns out that the problem was not really resolved after all.

Page © 2007 by the Trustees of Princeton University.
Content © 2007 by Scott Cromar. Used with permission.
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The Solaris Troubleshooting Blog

Power Mac G4: How to Differentiate Between Models

Power Mac G4: How to Differentiate Between Models.

When trying to identify the proper power supplies, it is tough with older Macs.  They may have been customized, but the reality of it is this.  Mac uses functional differences to differentiate between version of certain models.  So this two part article, (link above), covers identifying Apple Power Mac G4s.  The all pretty much look exactly the same.  Get the wrong piece of hardware, and it will not work.

Learn About Processors over the Weekend

So the assignment is to learn more about processors. It was suggested during Fridays lecture that a good source of information about hardware would be the hardware manufactures website. This is true. But what, where and how do you find that information. To start off I am going to walk you through using Google search and filtering the results. In the pursuit of this I hope to convey the ease and convenience of using the address bar, and tabbed browsing. For this tutorial to work for you properly it is suggested you use, Internet Explorer 8, Mozilla Firefox, Safari, or Opera as your web browser because these browsers support tabbed browsing.

Lets cover tabbed browsing first. Tabbed browsing is more efficient, and actually uses less system resources. More efficient because it allows the user to have for example, a tab that us open to Google and displaying search results. In a second tab, the user can be displaying the contents of the first web search result from the other tab. Sounds confusing but not really. Tabbed browsing uses less system resources because only one instance of the program is running. In windowed browsing a separate thread is started for that window.

The address bar is pretty much in the same location no matter what browser you use. Typically it is the long rectangle in the middle top of the browser. Here is a bit of experience. learn to use the address bar. it is your friend. A search engine will get you where you want to go most of the time. Others it is a waste of time. The address bar has also become more user-friendly. You no longer, and haven’t had too for a long time, know the whole web address or URL, examples are http://www.microsoft.com. When using the address bar all that is required is the name and what ever comes after the “.” example microsoft.com. If you type that in the address bar and hit enter the browser does the rest and will fill in the rest. While the site’s home page loads the address bar changes to reflect the actual URL of the page. example microsoft.com becomes http://www.microsoft.com/en/us/default.aspx.

Copying: Copying is also rather simple. First and foremost you must select something before you can copy it. Hear is 1 method, concerning text only.

left click and hold at the beginning or end of the text you wish to copy and drag the mouse over the rest of the text to select it. now to copy it.

Once you have a selection made it can be very frustrating to try to right-click for the copy function as the text can become unselected until the user is proficient with that style of interaction. Do the following instead. hold the “CTRL” key and tap the “C” key once. You have now copied your text.

To paste your copied text is also quite easy. Make sure your cursor is located where you want the text to be pasted. for instance. The cursor is blinking in the Google search engine. Where ever the cursor is that is where the text will be pasted.

(NOTE: This blog contains nomenclature particular to the web and especially technology.  There are certain conventions that are common.   These are not standardized, but knowing them helps when sifting through material. Example: Quotation marks are used to denote something that must be typed.  The quotation marks are nit included in the typing.  Navigation of menus and directories is shorthand most often.  It is assumed the reader has some level of ability.  Example: Open a new browser window by going to FILE–>NEW WINDOW. Means click on file menu click on new window. C:\Windows\System32\xxxxx.xxx, means, well I don”t care to type out two sentences for what you should know by now. These types of notations are the kinds you will see on this blog, in wiki results and other tech sites.  Try top learn them)

Now lets find a processor. Do the following to the letter.

1.) Open a browser that uses tabbed browsing. If it does not open to google.com go onto step 2, if so then skip to step 3

2.) In the address bar of the browser type “google.com” without the quotes.

3.) In the Google search box type, “Intel Pentium Processor” Your page should look like (Image 1).

Image1

4.) We want to view the shopping results only, this will give us a greater probability of finding a processor model number. Click on the 6th search result link called “shopping results for Intel Pentium processor” or the “shopping” filter in the top left area of the browser window.

5.) Now sort the list of processors by price from low to high, use the small drop down just below and to the right of the search box. (see Image 2)

6.) Select the heading of the 2nd result, remember, to select text, left click and hold at the beginning or end of the text you want. In this example we only want the search result heading. (see Image 2).

Image 2

7.) Now open a new tab ( either click on the little button to the right of the current tab (as seen in Image 3), or click FILE–>NEW–>NEW TAB.). The new tab opens next to the current one. Repeat steps 1-3, substituting what you type in 3 with pasting what you copied into the search field. Depending on your browser and system; the google search page will change as soon as you paste the heading into the search field.

Image 3

8.) Remove the last two words from the pasted phrase (see Image 4).

Image 4

9.) Now Right Click on the first link in the context menu click on “Open Link in New Tab” (see image 5)

Image 5

10.) a new tab opens next to the one your viewing. It is the specification page for the processor. Look closely at everything on the Intel page. There are several links that lead to much information. But there are also links that lead away from this processor into places that are not necessarily related to it. As a rule of thumb with Intel’s processor pages, the links that are on either side of the main content, which is always in the middle, are links to more information on that processor, and others like it. The links towards the top and bottom of the page generally lead to more company information.

There you have it. Several skill building exercises worked into one research assignment. I guarantee, if you develop the skills of tabbed browsing, copy and paste, and search filtering, you will save yourself hours of research overall, because you will not have to keep opening new searches because you have navigated away from your search results.

Good Luck Folks.

Here are a couple of processor models to investigate. I have purposefully not give full search terms with these processors. Use what you have just learned and learn more because of it.

Pentium QX9850
Intel X5570
Intel Pentium Dual Core T2200

Processor logic diagram

Take from an article on howstuffworks.com.

Microprocessor Logic

HowStuffWorks “Microprocessor Logic”

Below is a link to a very easy to read article on processor logic.  It is just one part of a larger HowStuffWorks.com.  The website howstuffworks.com is an excellent resource for bring class lectures full circle by having easy to understand articles, diagrams and videos of all the same subjects.  Enjoy the following read it will turn some lights on.

HowStuffWorks “Microprocessor Logic”.

 

Thanks,

BiS Techcenter Team

VIA VT6421A Serial RAID Controller – VIA Technologies, Inc.

VIA VT6421A Serial RAID Controller – VIA Technologies, Inc..

check this out.

Windows Taskbar – Windows 7 features – Microsoft Windows

Windows Taskbar – Windows 7 features – Microsoft Windows.

interesting read.

Processor Pins

So, why the increase in processor pins?

More pins allows for an increase in the Address bus and Data Bus.  Larger Data and Address Busses allow for smoother and faster performance.   With the ability to push more bits of information through the  processor it is able to crunch more numbers, thus allowing for more operations per clock cycle.  Increased pin counts also allow the processor to access larger amounts of memory.

So here is a side effect.  As pin counts went up so did heat.  As we moved into dual and quad core systems heat increased.   With AMD this became a  rather serious issue across some computer lines, especially laptops from Hp.

How did Intel overcome potential thermal problems as they moved from Dual-Core, through Core Duo and Core 2 Duo, into the I3′s, 5′s and 7′s, considering the sheer power of their new line?

check this out.

http://videos.webpronews.com/2009/01/20/ces-2009-intel-demonstrates-core-i7-core-centrino-2-and-atom-processor/

Evolution of the Video Card

Below are interfaces for video cards starting with ISA, ending in PCI Express.  In that order.  The evolution is more than merrily how the device is attached to a motherboard, there are technological advancements as well.  Faster on board memory.  The ability of the GPU to do more complex math, freeing the system processor up for more operations.  There is a lot there. Hopefully this will spark some discussion.

The images below are to show the connection type used for the card to interface with the motherboard.

VGA-8BIT-ISA

EISA VIDEO CARD

PCI Video Card 64meg

ATI Radeon x800

Nvidia Geforece GX 8800

What is a Computer Motherboard?

What is a Computer Motherboard?: How to Build a Custom PC Computer | eHow.com.

Found this great vid on ehow.com.

search terms used on a Google video search “motherboard parts”

choose the second result.