practice task
Find Which Process Owns a Port
Port 8080 is already in use and a new service will not start. You need to identify the listener before killing or reconfiguring anything.
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Try first
sudo ss -ltnp 'sport = :8080'Goal
Show the process name, PID, address, and port for the active listener.
Expected output
A listening socket row that includes Local Address:Port and process information such as users:(('node',pid=1234,fd=18)).
Teaches
A port conflict is a socket ownership problem. Identify the listener before changing service ports or stopping processes.
Common mistake
Killing the first process that looks related without proving it owns the exact listening socket.
check your answer
Answer key
What should your command prove?
A listening socket row that includes Local Address:Port and process information such as users:(('node',pid=1234,fd=18)).
How to explain it
A port conflict is a socket ownership problem. Identify the listener before changing service ports or stopping processes.
What to avoid
Killing the first process that looks related without proving it owns the exact listening socket.
command set
Commands to know
ss -ltnpsudo ss -ltnp 'sport = :8080'lsof -iTCP:8080 -sTCP:LISTEN
Related examples
answer check
Compare expected output
Open these command examples to compare your answer against realistic output.
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