The Importance of Network Testing
Every network engineer knows that proactively testing cables and switches is critical to maintaining a high-performing, reliable network. Just like regularly changing the oil in your car, proactive network maintenance helps identify and resolve small issues before they turn into major outages or performance impacts.
In this guide, you’ll learn:
- How to test a network cable and switch like a pro.
- Common network problems and how to test a network connection.
- Best practices and tools to streamline your maintenance routine.
By the end, you’ll be equipped to keep your network humming and avoid those dreaded after-hours support calls. Let’s get started!
Testing Network Switches
A comprehensive switch testing process should include:
- Visual Inspection. Check for physical damage, loose cables, and abnormal LED indicators; this is a good practice even with vendor-supplied management systems that monitor the devices. Ensure cooling fans are unobstructed and free from dust/debris. Having photographs of a switch’s physical condition stored in a shared location can be a useful practice to show “how it was” at a point in time
- Connectivity Testing. Use a tool like LinkSprinter to test port connectivity and availability of network services. For advanced diagnostics, use LinkRunner to analyze end-to-end paths and locate switch ports.
- Port Testing. Test individual ports for proper configuration (speed, duplex, VLAN configuration) and error rates.
- Performance Testing and Path Analysis. A periodic end-to-end performance test (such as the LinkRunner 10G can conduct) to validate available bandwidth, connection paths, and QoS can identify unplanned or undocumented changes in network configurations. A “soak test” (where test traffic is injected over a longer period of time) can reveal intermittent issues.
- Update Documentation – Document results and investigate any issues, ensuring that all test data is saved in a centralized system (such as Link-Live) where other team members can access and reference it; this can save significant “discovery time” when future problems occur.
Common Issues and Troubleshooting
Common switch issues include:
- Connectivity problems: Check cables, power, and port status
- Performance issues: Monitor for bottlenecks and check configurations
- Configuration errors: Audit settings and maintain backups
Cable issues often involve physical damage (which can occur over time due to vibration, extreme temperature changes, improper strain-relief or supports, or physical contact), incorrect wiring, or induced interference. Use an ethernet cable tester to diagnose faults and replace bad cables.
When troubleshooting, start with the physical layer and work up. Use tools to isolate the problem and document your findings.
Best Practices for Network Cable and Switch Maintenance
Proactive maintenance is key to ensuring the long-term reliability and performance of your network. Here are some best practices to keep in mind:
Regular Testing Schedules
- Test network cables and switches at least quarterly, more frequently for critical infrastructure
- Include visual inspections, cable and port testing, and configuration audits
- Use automated tools to streamline the process and ensure consistency
Cable and Switch Management
- Label all cables with a unique ID and purpose
- NEVER utilize a new patch cable without testing it (check for factory defects). Ensure mis-wired patch cords are disposed of or re-terminated and tested.
- Use cable management solutions to keep things neat and organized
- Maintain an up-to-date inventory of all switches and ports and their status, including open or available ports; unused ports should be disabled to prevent unauthorized connections.
- Keep accurate and up-to-date network diagrams and documentation (automated network discovery tools, such as in the LinkRunner AT 4000, speed and simplify this process.)
Updates and Documentation
- Regularly check for and apply firmware updates from switch vendors
- Always backup configurations before making changes
- Use change control processes to ensure awareness and consistency
- Regularly review and update documentation to identify any unwanted changes, or as the environment evolves
By following these best practices consistently, you can minimize downtime, improve security, and simplify ongoing management.
Conclusions
In this guide, we’ve covered the essentials of network cable and switch testing. You now know how and when to test a network cable, how to test a network switch, how to test a network connection, and what an ethernet cable tester is used for.
By implementing regular testing and following these best practices consistently, you can ensure your network remains reliable, secure, and high-performing. Proactively identifying and resolving issues before they cause downtime or disruption is key to keeping your business running smoothly.
By investing time and effort into testing and maintaining your network infrastructure, you can avoid costly outages, keep users productive, and ultimately drive organizational success.
Start putting these practices into action today and take control of your network’s health and performance. Your future self (and your organization) will thank you!
FAQs
Network Cables
How often should I test my network cables?
Test cables before and after installation, moves, or changes. For critical infrastructure, test annually or semi-annually. If you suspect issues, test immediately.
Can a bad network cable cause slow downs?
Yes, a faulty cable can cause packet loss, latency, and reduced throughput, slowing down performance. Regular testing and prompt replacement is crucial. Again, NEVER use new patch cords without testing them first.
How can I test Power over Ethernet (PoE) cables?
Use an ethernet cable tester that supports PoE, like the NetAlly LinkSprinter, to verify voltage and wattage for PoE devices. Here’s more info on how to do an easy PoE test under 10 seconds
Network Switches
How often should I test my network switches?
Test switches after deployment or administrative changes. Routine testing every 3-6 months is recommended, more frequently for critical environments.
Can a faulty switch cause network-wide issues?
Yes, a bad switch can cause connectivity loss, loops, broadcast storms, and security vulnerabilities across the network. Regular testing is essential.