Tag: linux

Proxychains-ng, Tor, and VPN+Tor combos tested honestly: which setups actually anonymize traffic and which are security theater you should stop trusting.

Bash does arithmetic natively, so you can drop bc for most math. Arithmetic expansion, conditions, bitwise operators, and the trap inside $(( )).

auditd logs every system call, file access, and command run on your Linux server. Learn ausearch, aureport, and how to write audit rules that catch it.

Ventoy turns any USB drive into a multi-boot drive, drop ISOs on it and boot any OS without re-flashing the drive each time.

set -euo pipefail makes your bash scripts fail fast instead of silently. Here's what each flag does and why they matter.

One syntax error in /etc/sudoers locks everyone out of root. Use visudo, read the syntax properly, avoid the common mistakes, and know what NOPASSWD gives.

awk is perfect for parsing logs. 5 patterns for filtering, summing, counting, splitting fields, and reformatting, no Perl or Python required.

jq is JSON on the command line. Here are 5 one-liners that actually solve real problems: filtering, extracting, transforming, combining, and debugging.

xargs and while read both loop over input, but they handle arguments, signals, and performance differently. Here's when to use each.

Environment variables live in five places on Linux: /etc/environment, ~/.bashrc, ~/.profile, systemd Environment=, and the shell. When to use each one.

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.

Understand sticky bit, setuid, and setgid: what they do, how to set them, security implications, and real-world use cases.