#troubleshooting
All articles tagged #troubleshooting — practical guides from production experience.
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68 posts tagged #troubleshooting · page 2 of 8
How to Restart Network Service in Linux (All Distros)
Restart network service in Linux using systemctl, nmcli, and ip commands — covering Ubuntu, RHEL, Debian, and CentOS with real examples and what to do when restart fails.
Port Already in Use Linux: How to Find and Fix It
Fix 'port already in use' errors on Linux — find what process owns the port, kill it safely, handle TIME-WAIT sockets, and prevent the issue from recurring.
ping vs curl vs telnet: Which to Use for Network Testing
Know when to use ping, curl, and telnet for network testing — what each tool tests, what its limitations are, and which to reach for first when debugging connectivity issues.
Permission Denied Linux: Fix with chmod and chown
Fix 'permission denied' errors in Linux — read permission bits correctly, use chmod and chown safely, debug with ls -la and stat, and avoid common mistakes that break applications.
Nginx 502 Bad Gateway Fix: Root Causes and Solutions
Fix nginx 502 bad gateway errors — identify the root cause from the error log, fix upstream connection issues, keepalive config, and timeout problems in production.
netstat vs ss: Which to Use and What's the Difference
netstat vs ss — understand the differences, when to use each, equivalent command translations, and why ss is the modern replacement for netstat on Linux.
How to Monitor Real-Time Logs in Linux: tail, journalctl, multitail
Monitor real-time logs in Linux using tail -f, journalctl -f, and multitail — follow multiple log files simultaneously, filter live output, and build production log monitoring workflows.
Linux tail Multiple Files: Real Examples and Techniques
tail multiple files in Linux simultaneously — using tail -f, multitail, and journalctl to monitor several log files at once in real production scenarios.
Linux sort Command: Real Usage Examples
Use the Linux sort command effectively — sort by column, numerically, by size, reverse order, deduplicate, and combine with other commands for real log and data analysis.