Troubleshooting Methodology Overview

Introduction

• Troubleshooting varies in difficulty based on familiarity with the network.
• Known networks are easier to troubleshoot than new ones.

Steps in Troubleshooting Methodology

1. Identify the Problem

• The user initiates the troubleshooting process by reporting an issue (e.g., "I can't access the internet").
• Service desk needs to gather more information to narrow down the symptoms.

2. Establish a Theory

• Formulate hypotheses based on network topology and user symptoms.
• Ask relevant questions:
  • Is the computer powered on?
  • Does it have an IP address?
  • Is the correct VLAN associated with the switch port?
  • Is trunking working on the switch?
  • Is the default gateway reachable?
  • Does Network Address Translation (NAT) function correctly?

3. Test the Theory

• Validate your theory by performing tests on suspected devices:
  • Can the device ping the default gateway?
  • Verify connectivity with other sites.

4. Solve the Problem

• Create a game plan for addressing the identified issue (e.g., NAT misconfiguration).
• Follow Change Control procedures for configuration changes.
• Authorize changes and implement them.
• Ensure that the solution restores connectivity and does not disrupt other functions.
• Document all changes and the solution process for future reference.

5. Repeat the Process

• Apply the same troubleshooting methodology to the next reported issue.

Conclusion

• Emphasizes the importance of documentation and systematic troubleshooting.
• Future videos will focus on detailed applications of each step, starting with identifying problems in specific network topologies.