Network Troubleshooting Guides
Expert step-by-step guides for diagnosing network issues. Each guide includes direct answers, numbered instructions, real examples, and links to free diagnostic tools.
Available Guides
- How to Check SSL Certificate Expiry - Learn to verify SSL/TLS certificate expiration dates, validate certificate chains, and set up monitoring to prevent downtime.
- DNS Propagation Troubleshooting - Diagnose DNS propagation issues, understand TTL settings, and verify records are resolving correctly across global regions.
- How to Read Traceroute Results - Master interpreting traceroute output to identify network bottlenecks, latency issues, and routing problems.
- How to Check if Ports are Open - Test TCP port accessibility, verify firewall rules, and troubleshoot connection issues to servers and services.
- How to Check if a Website is Down - Determine if a website is down for everyone or just you. Test from multiple locations to identify outages.
About These Guides
Each guide is written for both beginners and experienced network administrators. We provide the quick answer first, followed by detailed steps for those who need more context. All guides link to free ProbeOps diagnostic tools that test from 6 global locations.