Servers run Linux, and Linux is run from the shell. This playground teaches the day-to-day of administering a RHEL / CentOS box — files, permissions, users, services, and packages — with a real simulated terminal on every page. Type commands, break things, fix them. No VM, no SSH, no internet.
ls and press Enter. Then pwd, whoami, cat notes.txt,
cd projects. It's a working shell with a real filesystem.
Production Linux boxes are "headless" — no mouse, no windows. The shell is the only way in.
Red Hat Enterprise Linux & its rebuilds (CentOS, Rocky, Alma) power banks, telcos, and the cloud.
Docker, Kubernetes, Ansible, CI/CD — all sit on top of Linux skills you'll build here.
Every terminal in this pack is the same simulated server — a Red Hat Enterprise Linux 9 box you log into
as the user student. It has a home directory, some files and scripts, running services
(sshd, httpd, firewalld), and the dnf package manager.
You can even become root with sudo.
dnf, systemd, rpm). Learn one, you know them all.
What Linux is, the prompt, and your first commands: pwd, whoami, ls.
The / tree, where things live (/etc, /var, /home), and moving around.
Create, copy, move, delete, and read files with touch cp mv rm cat.
The editor on every server. The modal mental model, the core keys, and how to escape — in a real in-page vi simulator.
rwx, chmod octal, chown — with a live permission calculator.
useradd, sudo, /etc/passwd, and the wheel group.
ps, top, kill, and managing daemons with systemctl.
Install and remove software the RHEL way with dnf/yum and rpm.
grep, |, >, >> — the glue that makes the shell powerful.
A full terminal plus guided real-world scenarios to work through.
One-page reference plus tasks the terminal checks for you.
Saved in your browser — close the tab and come back where you left off.