Linux & DevOps Troubleshooting Blog
Practical guides for Linux engineers — NGINX debugging, process troubleshooting, CIS hardening, and production incident response.
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79 posts · page 6 of 9
Disk Full Linux: How to Clean Up and Free Space Fast
Fix a full disk on Linux fast — find what's taking space with df and du, clean logs, Docker, package caches, and deleted-but-open files in production.
How to Compress Files in Linux: tar Examples
Compress files in Linux with tar — create .tar.gz and .tar.bz2 archives, choose the right compression level, and handle common tar use cases with real examples.
How to Check Open Ports in Linux: ss vs netstat
Check open ports in Linux using ss and netstat — with real command examples, output explanation, and when to use each tool in production troubleshooting.
How to Check Network Interface in Linux: ip, ifconfig, ethtool
Check network interfaces in Linux with ip link, ip addr, and ethtool — see IP addresses, interface state, link speed, and diagnose interface-level network problems.
How to Check Listening Ports in Linux (2026 Guide)
Check listening ports in Linux with ss, netstat, lsof, and nmap — know which service owns each port, detect unexpected listeners, and troubleshoot connection refused errors.
How to Check Firewall Status in Linux: iptables, firewalld, ufw
Check firewall status in Linux using iptables, firewalld, and ufw — see active rules, verify port access, and diagnose whether firewall is blocking traffic.
Check Disk Usage in Linux: du vs df Explained
Check disk usage in Linux using df and du — understand the difference, read the output correctly, and find what's filling your disk with real command examples.
How to Check CPU Usage in Linux: Real Command Examples
Check CPU usage in Linux using top, mpstat, ps, and vmstat — read per-core breakdown, identify CPU-hungry processes, and diagnose high load in production.
Cannot Connect to Server Linux: Step-by-Step Troubleshooting
Troubleshoot 'cannot connect to server' on Linux — diagnose connection refused, timeout, and network unreachable errors with a systematic step-by-step approach.