XK0-006 System Management Practice Question

A process with PID 2345 is not responding. The administrator wants to force stop the process immediately. Which command should be used?

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

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kill -9 2345

SIGKILL (signal 9) forcefully terminates a process. kill -9 2345 sends SIGKILL to PID 2345.

Answer analysis

For each option: why learners choose it and why it is or isn't the right answer here.

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kill -9 2345
Why this is correct
SIGKILL (signal 9) cannot be caught, blocked or ignored by the process, so the kernel terminates PID 2345 immediately. This satisfies the requirement to force stop an unresponsive process, unlike the default SIGTERM sent by plain kill.
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kill -1 2345
Why it's wrong here
Signal 1 (SIGHUP) is a hangup that many daemons treat as a reload or terminate, but it does not guarantee immediate forced termination of an unresponsive process. It is tempting because it can end some processes, yet SIGKILL (signal 9) is the correct choice for an unresponsive PID.
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pkill -15 -f processname
Why it's wrong here
pkill -15 sends SIGTERM by name match, which a hung process can ignore, and it targets by pattern rather than the specified PID. It is tempting for bulk process management, but the scenario names PID 2345, so kill -9 2345 is the precise forced stop.
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kill -15 2345
Why it's wrong here
Signal 15 (SIGTERM) requests graceful termination and can be caught or ignored, so an unresponsive process may not stop. It is tempting as the default kill signal, but SIGKILL (signal 9) is required to force immediate termination of PID 2345.

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