Tag: sysadmin

Docker Volumes vs Bind Mounts: Where Your Data Actually Lives

Docker volumes vs bind mounts explained: named volumes, anonymous volumes, bind mounts, and tmpfs. Real examples for databases, dev workflows, and production.

Linux Audit Log: What's Really Happening on Your Server

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: Boot Any OS, Any Time

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.

The sudoers Mistake Everyone Makes Once

Never edit /etc/sudoers directly. One syntax error locks everyone out. Use visudo, understand NOPASSWD risks.

Certificate Expiry: Monitor Before the 3 AM Call

Certs expire silently. Check expiry with openssl, automate renewal checks with cron, get alerts before disaster.

Where Environment Variables Actually Live in Linux

Navigate /etc/environment, ~/.bashrc, ~/.profile, and systemd Environment=. When to use each.

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.

Docker CMD vs ENTRYPOINT: The Final Answer

CMD and ENTRYPOINT work together. Learn the difference, exec vs shell form, and when to use the combo pattern.

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.