Listening on a local TCP port | LPIC-1 102-500 Exam original practice question

109.3Standard

Use OpenBSD nc to listen on local TCP port 8080.

Do not use UDP mode or remote scan mode.

Which command is appropriate?

Hint 1: Focus on the requirement

Identify what must change and what must remain unchanged. Then choose the command whose scope matches that requirement.

Hint 2: Check each command's role

Separate commands that display information, change state, remove data, or affect a child process.

nc -z 127.0.0.1 8080: Incorrect. -z tests a port as a client and does not listen.
nc -u -l 8080: Incorrect. -u selects UDP listen mode.
nc -v 8080: Incorrect. It lacks a listen option and a complete destination form.
nc -l 8080: Correct. It listens for TCP connections on local port 8080.

Detailed explanation

Incorrectnc -z 127.0.0.1 8080

Incorrect. -z tests a port as a client and does not listen.

Incorrectnc -u -l 8080

Incorrect. -u selects UDP listen mode.

Incorrectnc -v 8080

Incorrect. It lacks a listen option and a complete destination form.

Correctnc -l 8080

Correct. It listens for TCP connections on local port 8080.

An example you can run in a temporary verification environment.

printf '%s
' '-l=listen' 'no -u=TCP' '8080=local port'

-l=listen
no -u=TCP
8080=local port

Foundation review

Check whether the command acts on the current shell, a new process, an existing process, or a file.

Use the supplied command and compare the output with the expected result.

Question IDKP-109-832

EnvironmentOpenBSD netcatのoption対応表（socket作成なし）

Last technical review2026-08-13