5.1 – Troubleshooting
Network Troubleshooting Methodology
Network professionals solve problems every day. In this video, you’ll learn how a troubleshooting methodology can simplify complex issues and make it easier to identify and solve big problems.
5.2 – Physical Issues
Cable Issues
If the physical layer isn’t right, the network will have big problems. In this video, you’ll learn about fiber mismatches, cable categories, crosstalk, EMI, attenuation, and proper termination.
Interface Issues
A network interface can tell a lot about the health of the network. In this video, you’ll learn about interface monitoring, CRC errors, runts, giants, drops, error disabled states, and port status messages.
Hardware Issues
A single hardware issue can cause signficant problems on a production network. In this video, you’ll learn about PoE standards, transceiver mismatches, and how to calculate transceiver signal strength.
5.3 – Troubleshooting Network Services
Switching Issues
An incorrectly configured switch can be a critical error. In this video, you’ll learn about stopping switching loops with spanning tree protocol, managing VLAN assignments, and best practices for configuring access control lists.
Routing and IP Issues
Configuring a router incorrectly can cause a number of network issues. In this video, you’ll learn about routing tables, the gateway of last resort, address pool exhaustion, and troubleshooting duplicate IP addresses.
5.4 – Performance Issues
Performance Issues
There’s never enough bandwidth. In this video, you’ll learn how to troubleshoot congestion, bottlenecks, latency, packet loss, and jitter.
Wireless Issues
It’s difficult to troubleshooting something you can’t see. In this video, you’ll learn how to resolve wireless interference, manage channel usage, resolve roaming misconfigurations, and more.
5.5 – Tools and Protocols
Software Tools
Most network administrators have many tools at their disposal. In this video, you’ll learn about protocol analyzers, port scanners, device discovery, and speed test sites.
Command Line Tools
All of the detailed troubleshooting tools are at the command line. In this video, you’ll learn about ping, traceroute, nslookup, dig, tcpdump, netstat, and more.
Hardware Tools
A good toolbag contains many different hardware tools. In this video, you’ll learn about tone generators, cable testers, taps, port mirror, wi-fi analyzers, and more.
Basic Network Device Commands
Some commands are the same across multiple devices. In this video, you’ll learn about show route, show interface, show config, and other common device commands.