■ linux.opperiesen.com opperiesen.com ↗

linux quest

learn the shell in 144 small missions.
no videos. nothing runs on your machine.

Built for the awkward bit before man pages become useful: knowing what to ask for.

0/144missions

24chapters

0%complete

start here

Progress stays in this browser.

Chapters

144 missions

guest@quest simulated · local only

guest@quest:~$

mission 01

mission checklist

0/0

Each step checks both the result and the Linux method being practiced.

mission complete

The shell did exactly what you asked.

why this matters

workspace ~

working notes

Commands, without the wall of text.

Move

pwd: where am I?
ls -la: list all with metadata
cd path: change directory
*, ?: match path names

Files

mkdir -p dir: create a tree
cp -r a b: copy recursively
mv a b: move or rename
ln -s a b: create a symbolic link

Read & find

head / tail: sample either end
grep -rn text dir: search content
find . -type f: search paths
man command: open its manual

Streams

a | b: pipe stdout into stdin
> / >>: write / append stdout
< file: read stdin from file
2> file: write stderr

Text

sort | uniq -c: group and count
cut -d: -f1: select fields
sed / awk: transform records
xargs command: turn input into args

Shell

source file: load shell settings
alias ll='ls -la': name a shortcut
test -f file: check a condition
read NAME: read from stdin

Compare

file path: identify content
cmp a b: compare bytes
diff -u a b: show line changes
sha256sum -c file: verify integrity

Access

stat path: inspect metadata
chmod 640 file: set exact mode
chown user:group: change ownership
id / groups: inspect identity

Operate

ps / top / pkill: inspect and stop processes
nice / renice: adjust priority
jobs / bg / fg: control shell jobs
nohup / wait: detach or wait

Network

ss -lnt: list listening ports
getent / dig: resolve names
traceroute / nc: trace and probe
wget / curl: fetch a resource

Sync & keys

ssh-keygen: create or inspect a key
rsync -av a b: sync a tree
ssh host: open a remote shell
scp a host:path: copy over SSH

Paths & storage

realpath path: resolve an absolute path
mktemp: create a safe temp file
findmnt / blkid: inspect filesystems
mount / umount: attach or detach one

Services

apt install pkg: install software
systemctl status: inspect a unit
systemctl enable: start it at boot
journalctl -u: read unit logs