Troubleshooting Network Connectivity

Troubleshooting Network Connectivity

1h 10mIntermediate2016-09-28

Authors

Greg Sowell

Greg Sowell

Providing networking advice to datacenters, banks, and NBA franchises

Course details

"The Internet is down" is the last thing any network admin wants to hear. But failures are bound to happen to any network, whether enterprise, small business, or home. This course shows how to diagnose the source of the problem by analyzing what works and what doesn't work, layer by layer, and explains how to fix each type of problem. Greg Sowell shows how to troubleshoot physical media (e.g., copper and fiber), kill rogue DHCP servers, and understand how switching loops and DNS issues start. Plus, learn how to troubleshoot Wi-Fi interference, verify sockets, use packet capture to verify network operations, and change pivot from reactive to proactive remedies with a network management system (NMS) and inexpensive probes.

Even if you're rusty on your OSI model knowledge, this course is invaluable if you're having trouble with your network. It offers a clear, practical troubleshooting guide to narrowing down and solving most problems related to network connectivity.

Learning objectives
Troubleshooting the physical layer: POTS, Ethernet, and more
Troubleshooting the data link layer
Troubleshooting the network layer
Troubleshooting the transport layer
Troubleshooting Wi-Fi
Troubleshooting proactively

Skills covered

ProjectNetwork AdministrationNetwork and System Administration

Concepts

Introduction

  • Introduction
  • What you should know
  • Tools and software

Physical Layer Troubleshooting

  • POTS failure
  • Copper Ethernet failure
  • Fiber interface failure

Data Link and Network Layer Troubleshooting

  • Switching loop
  • Duplicate addressing
  • DNS IP addressing issues
  • Rogue DHCP
  • Failed routes routing loop

Transport Layer Troubleshooting

  • Port already in use, netstat
  • Test service connectivity, telnet wireshark

Wi-Fi Troubleshooting

  • Intermittent service

Proactive Troubleshooting

  • NMS
  • Probes

Conclusion

  • Next steps
40,000 Toman