Run ss -tulpn | tee lab/listeners.txt.
ss -tulpn | tee lab/listeners.txt
Click any instruction for the command details, the why, and the common mistake to avoid.
Run ss -tulpn | tee lab/listeners.txt.
ss -tulpn | tee lab/listeners.txt
Run cat lab/listeners.txt.
cat lab/listeners.txt
Run wc -l lab/listeners.txt.
wc -l lab/listeners.txt
Create a free account to sync completed lessons, XP, streaks, course status, and your next lesson across sessions.
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Progress sync stores completion IDs, scores, streaks, badges, and game settings. Terminal contents, editor snippets, lab scratch, email, and real names are never published on leaderboards or share cards.
Capture and inspect listener baseline output.
Run the commands in order and compare the outputs.
Junior operators build confidence by gathering evidence before changing systems.
cat <file>
Print text file contents.
tee <file>
Write piped text to a lab file and keep it on screen.
ss|ip
Inspect simulated sockets and addresses.
ssh|scp|ssh-keygen
Practice SSH inspection and dry-run transfer shapes without network access.