Checking TCP listeners and processes | LinuC Level 1 102 Exam original practice question

1.10.1Basic

Use ss to list listening TCP sockets numerically and show associated processes where permitted.

Which command is appropriate?

Hint 1: Focus on the requirement

Separate the scope and side effects of the concepts before comparing the choices.

Hint 2: Key terms

Review the short definitions of the command, configuration, and security concepts involved.

ss: A Linux command for inspecting TCP and UDP socket states.
listening socket: A socket waiting to accept incoming connections.
TCP: A connection-oriented transport protocol that tracks communication state.
UDP: A datagram transport protocol that does not establish a connection first.
process mapping: The association between a socket and the process using it.
numeric output: Output that keeps service and host values as numbers instead of names.

Detailed explanation

Correctss -lntp

Correct. It lists numeric listening TCP sockets and process information.

Incorrectss -ant

Incorrect. It includes non-listening TCP sockets and omits process information.

Incorrectss -lnup

Incorrect. It targets UDP sockets.

Incorrectss -s

Incorrect. -s shows a summary rather than individual listeners.

An example you can run in a temporary verification environment.

ss --help 2>&1 | grep -E -- '-l|--listening|-p|--processes' | head -n 4

listeningとprocessesに関するhelp行

Foundation review

A mode bit controlling read, write, execute, or special execution behavior.

Attributes that determine whether a password or login account can be used.

A per-process or per-user ceiling such as open files or process count.

Question IDKL-102-1119

Environmentiproute2 ss help / socket照会のみ

Last technical review2026-08-13

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