# IT Fundamentals/Troubleshooting

This lesson introduces IT troubleshooting methodology.

## Objectives and Skills

Objectives and skills for the troubleshooting portion of IT Fundamentals certification include:
* Explain the troubleshooting methodology.
** Identify the problem
*** Gather information
*** Duplicate the problem, if possible
*** Question users
*** Identify symptoms
*** Determine if anything has changed
*** Approach multiple problems individually
** Research knowledge base/ Internet, if applicable
** Establish a theory of probable cause
*** Question the obvious
*** Consider multiple approaches
**** Divide and conquer
** Test the theory to determine the cause
*** Once the theory is confirmed (confirmed root cause), determine the next steps to resolve the problem
*** If the theory is not confirmed, establish a new theory or escalate
** Establish a plan of action to resolve the problem and identify potential effects
** Implement the solution or escalate as necessary
** Verify full system functionality and, if applicable, implement preventive measures
** Document findings/lessons learned, actions, and outcomes

## Readings

* Wikipedia: Troubleshooting

## Multimedia

* YouTube: Troubleshooting Methodology
* YouTube: Chapter 13 - IT Fundamentals+ (FC0-U61) IT Troubleshooting

## Activities

* Select a recent or frequent technology problem you have had at school, work, or home. Explain how you would solve the problem following the troubleshooting methodology. Include the problem description and symptoms, resources searched, theories tested, problem resolution, and how you would document the issue and prevent it from recurring.
* Test Internet connectivity:
** Verify a physical connection:
*** Wired: Check for connectivity lights on the network adapter and switch or router.
*** Wireless: Check for connectivity through the user interface.
** Verify ip address settings.
*** Windows: Use ipconfig.
*** macOS: Use Network Utility, System Preferences / Network, or ifconfig.
*** Linux: Use Network Configuration, System Settings / Networking, or ifconfig.
** Review Ping/Host. Verify local and remote connectivity using ping.
*** Ping your local IP address.
*** Ping your local default gateway address.
*** Ping an Internet host such as 8.8.8.8.
** Review Nslookup. Verify name resolution using nslookup and an Internet host name, such as en.wikiversity.org.
* View system recovery options.
** All: Review Wikipedia: Single-user mode.
** Windows: Boot into Safe Mode and/or the Recovery Console. View available options but do not make any changes. Restart the system normally when you are finished.
** macOS: Boot into single-user mode. View available options but do not make any changes. Restart the system normally when you are finished.
** Linux: Boot into single-user mode. View available options but do not make any changes. Restart the system normally when you are finished.

## Lesson Summary
### Troubleshooting

* Troubleshooting is a form of problem solving, often applied to repair failed products or processes on a machine or a system. It is a logical, systematic search for the source of a problem in order to solve it, and make the product or process operational again. Troubleshooting is needed to identify the symptoms. Determining the most likely cause is a process of elimination—eliminating potential causes of a problem. Finally, troubleshooting requires confirmation that the solution restores the product or process to its working state.

### Troubleshooting Methodology

* Troubleshooting methodology includes:
* Identify the problem
** Gather information
** Duplicate the problem, if possible
** Question users
** Identify symptoms
** Determine if anything has changed
** Approach multiple problems individually
* Research knowledge base/ Internet, if applicable
* Establish a theory of probable cause
** Question the obvious
** Consider multiple approaches
*** Divide and conquer
* Test the theory to determine the cause
** Once the theory is confirmed (confirmed root cause), determine the next steps to resolve the problem
** If the theory is not confirmed, establish a new theory or escalate
* Establish a plan of action to resolve the problem and identify potential effects
* Implement the solution or escalate as necessary
* Verify full system functionality and, if applicable, implement preventive measures
* Document findings/lessons learned, actions, and outcomes

## Key Terms
### EMI (Electromagnetic Interference)

    A disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction.

### ESD (Electrostatic Discharge)

    The sudden flow of electricity between two electrically charged objects caused by contact, an electrical short, or dielectric breakdown.

### safe mode

    A diagnostic mode of a computer operating system. In Windows, safe mode only allows essential system programs and services to start up at boot. It is widely used for removing rogue security software.

### single user mode

    A mode in which a multiuser computer operating system boots into a single superuser, common on Unix-like systems including macOS and Linux.

## Assessments

* Flashcards: Quizlet: IT Fundamentals - Troubleshooting
* Quiz: Quizlet: IT Fundamentals - Troubleshooting

## See Also

* Computer Support