1. OV 15 - 1 Copyright © 2013 Logical Operations, Inc. All rights reserved. Network Troubleshooting  Network Troubleshooting Models  Network Troubleshooting Utilities  Hardware Troubleshooting Tools  Common Connectivity Issues

2. OV 15 - 2 Copyright © 2013 Logical Operations, Inc. All rights reserved. Troubleshooting Recognition Diagnosis Resolution

3. OV 15 - 3 Copyright © 2013 Logical Operations, Inc. All rights reserved. Troubleshooting Models Step-by-step approach Administrator

4. OV 15 - 4 Copyright © 2013 Logical Operations, Inc. All rights reserved. The Network+ Troubleshooting Model 1. Identify the problem 2. Establish a theory of probable cause 3. Test the theory to determine cause 4. Establish a plan of action to resolve the problem and identify potential effects 5. Implement the solution or escalate as necessary 6. Verify full system functionality and if applicable implement preventative measures 7. Document findings, actions, and outcomes

5. OV 15 - 5 Copyright © 2013 Logical Operations, Inc. All rights reserved. Step 1: Identify the Problem 1. Identify the problem  Question users  Re-create the problem  Identify symptoms  Determine if anything has changed 2. Establish a theory of probable cause 3. Test the theory to determine cause 4. Establish a plan of action to resolve the problem and identify potential effects 5. Implement the solution or escalate as necessary 6. Verify full system functionality and if applicable implement preventative measures 7. Document findings, actions, and outcomes

6. OV 15 - 6 Copyright © 2013 Logical Operations, Inc. All rights reserved. Step 2: Establish a Theory of Probable Cause 1. Identify the problem 2. Establish a theory of probable cause  Question the obvious 3. Test the theory to determine cause 4. Establish a plan of action to resolve the problem and identify potential effects 5. Implement the solution or escalate as necessary 6. Verify full system functionality and if applicable implement preventative measures 7. Document findings, actions, and outcomes

7. OV 15 - 7 Copyright © 2013 Logical Operations, Inc. All rights reserved. Step 3: Test the Theory to Determine Cause 1. Identify the problem 2. Establish a theory of probable cause 3. Test the theory to determine cause  Determine next steps to resolve the problem 4. Establish a plan of action to resolve the problem and identify potential effects 5. Implement the solution or escalate as necessary 6. Verify full system functionality and if applicable implement preventative measures 7. Document findings, actions, and outcomes

8. OV 15 - 8 Copyright © 2013 Logical Operations, Inc. All rights reserved. Step 4: Establish a Plan of Action to Resolve the Problem and Identify Potential Effects 1. Identify the problem 2. Establish a theory of probable cause 3. Test the theory to determine cause 4. Establish a plan of action to resolve the problem and identify potential effects  Establish a plan of action before you start making changes, once you have determined the probable cause  Detail each step that you will take while attempting to resolve the issue 5. Implement the solution or escalate as necessary 6. Verify full system functionality and if applicable implement preventative measures 7. Document findings, actions, and outcomes

9. OV 15 - 9 Copyright © 2013 Logical Operations, Inc. All rights reserved. Step 5: Implement the Solution or Escalate as Necessary 1. Identify the problem 2. Establish a theory of probable cause 3. Test the theory to determine cause 4. Establish a plan of action to resolve the problem and identify potential effects 5. Implement the solution or escalate as necessary  Implement the plan of action step by step to fix the problem  Or, escalate the issue to the appropriate personnel 6. Verify full system functionality and if applicable implement preventative measures 7. Document findings, actions, and outcomes

10. OV 15 - 10 Copyright © 2013 Logical Operations, Inc. All rights reserved. Step 6: Verify Full System Functionality and If Applicable Implement Preventative Measures 1. Identify the problem 2. Establish a theory of probable cause 3. Test the theory to determine cause 4. Establish a plan of action to resolve the problem and identify potential effects 5. Implement the solution or escalate as necessary 6. Verify full system functionality and if applicable implement preventative measures 7. Document findings, actions, and outcomes

11. OV 15 - 11 Copyright © 2013 Logical Operations, Inc. All rights reserved. Step 7: Document Findings, Actions, and Outcomes 1. Identify the problem 2. Establish a theory of probable cause 3. Test the theory to determine cause 4. Establish a plan of action to resolve the problem and identify potential effects 5. Implement the solution or escalate as necessary 6. Verify full system functionality and if applicable implement preventative measures 7. Document findings, actions, and outcomes

12. OV 15 - 12 Copyright © 2013 Logical Operations, Inc. All rights reserved. Troubleshooting with IP Configuration Utilities Incorrect IP configuration

13. OV 15 - 13 Copyright © 2013 Logical Operations, Inc. All rights reserved. The ping Utility Ping to local system succeeds Ping to local system succeeds Ping to default gateway fails

14. OV 15 - 14 Copyright © 2013 Logical Operations, Inc. All rights reserved. The traceroute Utility Start troubleshooting at last valid connection Start troubleshooting at last valid connection

15. OV 15 - 15 Copyright © 2013 Logical Operations, Inc. All rights reserved. The arp Utility Incorrect IP address mapping

16. OV 15 - 16 Copyright © 2013 Logical Operations, Inc. All rights reserved. The NBTSTAT Utility Service running optimally Service running optimally

17. OV 15 - 17 Copyright © 2013 Logical Operations, Inc. All rights reserved. The NETSTAT Utility Queue shows activity No adapter errors Connection valid Listening ports valid Listening ports valid

18. OV 15 - 18 Copyright © 2013 Logical Operations, Inc. All rights reserved. The Nslookup Utility Verify default server Verify that server is responding to queries Verify that server can resolve names

19. OV 15 - 19 Copyright © 2013 Logical Operations, Inc. All rights reserved. SNIPS System and Network Integrated Polling System (SNIPS) offers:  Monitoring of UNIX systems  Command-line and web interfaces  Monitoring functions for network services  Determine status  Report  Real-time reports  Alarms and logs  Four supported monitoring levels:  Info  Warning  Error  Critical

20. OV 15 - 20 Copyright © 2013 Logical Operations, Inc. All rights reserved. Network Technician's Hand Tools

21. OV 15 - 21 Copyright © 2013 Logical Operations, Inc. All rights reserved. Electrical Safety Rules Electrical safety rules:  Professionals should service high-power equipment  Always disconnect before servicing  Work with a partner  Never bypass safety devices  Use anti-static devices  Perform only the work for which you have sufficient training  Do not attempt repair work when you are tired  Do not assume anything without checking it out for yourself  Do not wear jewelry or other articles that could accidentally contact circuitry and conduct current

22. OV 15 - 22 Copyright © 2013 Logical Operations, Inc. All rights reserved. Electrical Safety Rules (Cont.) Electrical safety rules:  Wear rubber-soled shoes to insulate yourself from ground  Suspend work during an electrical storm  Do not handle electrical equipment when your hands or feet are wet or when you are standing on a wet surface  Prevent static electricity from damaging components by standing on a totally insulated rubber mat to increase the resistance of the path to ground

23. OV 15 - 23 Copyright © 2013 Logical Operations, Inc. All rights reserved. Wire Crimpers Used to trim the ends of a cable

24. OV 15 - 24 Copyright © 2013 Logical Operations, Inc. All rights reserved. Punch Down Blocks There are two types of punch down blocks:  66 Block - Used for terminating telecommunications  110 Block - Used for structured wiring systems

25. OV 15 - 25 Copyright © 2013 Logical Operations, Inc. All rights reserved. Punch Down Tools Strips insulation and embeds wire

26. OV 15 - 26 Copyright © 2013 Logical Operations, Inc. All rights reserved. Circuit Testers Displays circuit status Plugs into socket

27. OV 15 - 27 Copyright © 2013 Logical Operations, Inc. All rights reserved. Multimeters DigitalAnalog

28. OV 15 - 28 Copyright © 2013 Logical Operations, Inc. All rights reserved. Cable Testers Adapters for different network types Displays media status Ports for network cable

29. OV 15 - 29 Copyright © 2013 Logical Operations, Inc. All rights reserved. Cable Certifiers Cable Certifiers are:  Used to perform tests  Cable testing  Validity testing  Useful in finding short circuits and other faults  Helpful in determining mode of connectivity devices  Full duplex  Half duplex

30. OV 15 - 30 Copyright © 2013 Logical Operations, Inc. All rights reserved. Types of Cable Testers and Certifiers Tester or CertifierDescription Certification tester  Determine if network meets ISO or TIA standards (Cat 5e, Cat 6  or Cat7)  Use when copper and fiber media exist on network Qualification tester  Measure possible network data speeds  Used for troubleshooting LAN testers  Test network speed, cable skew, cable propagation delay, cable,  attenuation, and cable verification Network cable certifier  Test network speed and performance

31. OV 15 - 31 Copyright © 2013 Logical Operations, Inc. All rights reserved. Crossover Cables Wires crossed over internally

32. OV 15 - 32 Copyright © 2013 Logical Operations, Inc. All rights reserved. Hardware Loopback Plugs Crosses over transmit/receive lines

33. OV 15 - 33 Copyright © 2013 Logical Operations, Inc. All rights reserved. Time-Domain Reflectometers Time-Domain Reflectometers:  Used for detecting cable problems  Sends an electrical signal out onto the wire and analyzes the signal on its return  Can detect:  Bends  Short circuits  Connector problems  Termination problems on coax networks Optical TDRs used for fiber optic cabling:  Detect fiber length  Determine location of faulty splices, breaks, and bends  Measure attenuation

34. OV 15 - 34 Copyright © 2013 Logical Operations, Inc. All rights reserved. Tone Generators and Tone Locators Probe detects signal Tone generatorTone locator Port for network cable

35. OV 15 - 35 Copyright © 2013 Logical Operations, Inc. All rights reserved. Environment Monitors Environment monitors help maintain proper operational environment for network equipment:  Humidity  Temperature

36. OV 15 - 36 Copyright © 2013 Logical Operations, Inc. All rights reserved. Butt Sets

37. OV 15 - 37 Copyright © 2013 Logical Operations, Inc. All rights reserved. LED Indicators Link indicator Activity indicator

38. OV 15 - 38 Copyright © 2013 Logical Operations, Inc. All rights reserved. Network Analyzers Captures frames Displays captured frames and content Displays captured frames and content

39. OV 15 - 39 Copyright © 2013 Logical Operations, Inc. All rights reserved. Demarc Responsibility of the Phone Company Responsibility of the Property Owner Outside Wire Inside Wire Wire distribution device Demarcation point

40. OV 15 - 40 Copyright © 2013 Logical Operations, Inc. All rights reserved. Wireless Testers Wireless testers are:  Wi-Fi spectrum analyzers used for detecting problems on WLANs  Able to detect:  Wireless devices  Points of interference  Overall health of the WLAN

41. OV 15 - 41 Copyright © 2013 Logical Operations, Inc. All rights reserved. WLAN Survey Software WLAN survey software:  Used for:  Wireless planning  Simulations  Implementations  Simulates WLAN performance  Can determine network coverage areas

42. OV 15 - 42 Copyright © 2013 Logical Operations, Inc. All rights reserved. Physical Issues Physical connectivity issues include:  Crosstalk  Near-end crosstalk  Attenuation  Collisions  Shorts  Open impedance mismatches  Interference  Bad modules (SFPs, GBICs)  Cable problems

43. OV 15 - 43 Copyright © 2013 Logical Operations, Inc. All rights reserved. Logical Issues Logical connectivity issues include:  Port speed  Port duplex mismatches  Incorrect VLAN assignment  Incorrect IP address  Wrong gateway assignment  Wrong DNS server assignment  Wrong subnet mask

44. OV 15 - 44 Copyright © 2013 Logical Operations, Inc. All rights reserved. Wireless Issues Wireless connectivity issues include:  Interference  Incorrect encryption levels  Channel congestion  Incorrect frequency  SSID mismatches  Standard mismatches  Distance  Bounce  Incorrect antenna placement  Configurations  Incompatibilities  Incorrect channel  Latency  Incorrect switch placement

45. OV 15 - 45 Copyright © 2013 Logical Operations, Inc. All rights reserved. Routing and Switching Issues Routing and switching issues that might need to be escalated include:  Switching loop  Routing loop  Routing problem  Proxy arp  Broadcast storms  Port configuration  VLAN assignment  Mismatched MTU/MUT blackhole

46. OV 15 - 46 Copyright © 2013 Logical Operations, Inc. All rights reserved. Reflective Questions 1.In your troubleshooting experience, what types of problems have you encountered? How did you diagnose the problems? 2.In your opinion, what are the common TCP/IP issues that you encounter during troubleshooting?