The sudoers Mistake Everyone Makes Once
Never edit /etc/sudoers directly. One syntax error locks everyone out. Use visudo, understand NOPASSWD risks.
Tag: linux
All the articles with the tag "linux".
jq One-Liners Every Sysadmin Needs
jq is JSON on the command line. Here are 5 one-liners that actually solve real problems: filtering, extracting, transforming, combining, and debugging.
xargs vs while read: Which One and When
xargs and while read both loop over input, but they handle arguments, signals, and performance differently. Here's when to use each.
Where Environment Variables Actually Live in Linux
Navigate /etc/environment, ~/.bashrc, ~/.profile, and systemd Environment=. When to use each.
The Firewall Rule Order That's Breaking Your Setup
Firewall rules are evaluated top-down, first match wins. One misplaced ALLOW rule above your denials silently defeats all your security. Here's the fix.
Sticky Bit, Setuid, Setgid: Linux Special Permissions Explained
Understand sticky bit, setuid, and setgid: what they do, how to set them, security implications, and real-world use cases.
Is fail2ban Actually Working? Here's How to Check
Verify fail2ban is protecting you: check jails, test bans, monitor logs, common misconfiguration, and unban IPs when needed.
Diagnosing Slow Linux Boot with systemd-analyze
Your Linux box takes forever to boot? systemd-analyze shows exactly which services drag it down. Read blame, critical-chain, plot, and fix the slow ones.
SSHFS: Ditch SCP & Access Remote Files
SSHFS mounts remote filesystems over SSH so you can browse and edit files locally — faster than scp for interactive work.
How to Actually Read `systemctl status` Output
Decode systemctl status: Active state, CGroup processes, recent logs, loaded/enabled state. What each field tells you.
SSH Agent Forwarding: How It Works
Understand SSH agent forwarding security risks. When it's safe (almost never), and better alternatives like ProxyJump for jump hosts.
Is Your Linux Server Destroying Its SSD?
Check SSD health, find excessive write patterns, use noatime, move logs to tmpfs to extend lifespan.