Lab — Terminal Practice

The project is a tiny incident-notes layout: a working directory, a notes file you wrote, a backup copy, and an archive/ folder. That pattern shows up in real investigations (working copy vs preserved copy). It belongs under $HOME because Module 1 put user files in /home, not in /, /etc, or /tmp. /tmp can vanish on reboot. /etc is configuration. / is the entire tree.

Name things on purpose: notes.txt is the living document; notes.bak or archive/notes-copy.txt is the freeze. If you only ever have one file and you edit it forever, you cannot answer "what did we know at 14:00?" Version discipline starts with cp, not with Git — though Git comes later in real jobs.

Isolation is part of the lab design. Everything you create should be deletable with rm -ri on that folder alone. If your "lab" sprawls into Downloads, Desktop, and /opt, you will eventually rm the wrong relative path. One root folder under $HOME is a blast-radius control.

mkdir -p $HOME/cyberlium-lab/archive creates parents as needed and does not fail if the directory exists. cd into the lab, pwd to confirm, then create notes with nano or echo. cat the file. cp notes.txt archive/notes.bak. ls -la both locations. The verify loop (do, then ls/cat) is how professionals catch typos before mv/rm.

Relative paths are power tools: from inside cyberlium-lab, archive/notes.bak is clear. Absolute paths are safer in scripts and when you are lost: $HOME/cyberlium-lab/notes.txt. If pwd surprises you, stop inventing ../.. chains — pwd, then cd to a known absolute place. Guessing with .. is how people leave home and edit /.

mv renames or relocates; rm deletes. For this lab, prefer cp for the backup, keep the original, and only rm throwaway scratch files you created seconds ago. Interactive rm -i is a training wheel worth keeping while you build muscle memory. Never practice rm -rf / or rm -rf /* — not even "as a joke" on a machine without a snapshot.

Done means: cyberlium-lab exists; notes.txt has at least three lines you wrote; archive/ holds a copy; ls -la shows both; you can explain which file is working vs preserved. Bonus: a short README.txt describing the layout. Not done: files scattered in /, sudo mkdir under /opt for homework, or "I deleted it to clean up" with no copy.

Permissions preview (Module 3): keep the lab owner-writable; do not chmod 777 the tree. If you cannot write in your own home directory without sudo, fix the environment — do not sudo every mkdir forever. Daily sudo for home files is a smell.

Ethics: only your VM, WSL, or spare machine. Do not build the lab in a shared account's home. Do not "organize" someone else's Desktop with mv. Terminal skills without boundaries become vandalism.

Timebox the lab: twenty focused minutes of mkdir/cp/ls beats two hours of decorating filenames. If nano feels awkward, use a short heredoc like the code block below — the skill is path discipline, not editor fandom. When you finish, leave the tree in place; later modules will drop scripts and fake logs into the same cyberlium-lab root so your notes compound instead of scattering.

Type these on your machine. After mkdir and cp, run the verify commands even if you feel sure. The lab grades habits, not speed.

mkdir -p "$HOME/cyberlium-lab/archive"
cd "$HOME/cyberlium-lab" || exit 1
pwd

cat > notes.txt << 'EOF'
Cyberlium lab notes
- working copy lives here
- backups go under archive/
EOF

cp -v notes.txt archive/notes.bak
ls -la
ls -la archive/
cat notes.txt
cat archive/notes.bak

echo "Layout: notes.txt = working; archive/ = preserved copies" > README.txt

rm -rf /
mkdir /cyberlium-lab   # stay under $HOME
chmod -R 777 /

You now have a real lab home: folders, a working note, a preserved copy, and a verify habit. Module 2's commands only matter when they build something you can trust. Next up — Quiz — Basic Commands — checks navigation and file ops without the folder in front of you.