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How do you list listening ports on Linux in an interview?
How do you list listening ports on Linux in an interview? Use ss -tulnp and compare the result to a known baseline. On a lab web server you expect sshd and the web service, not a strange high port. “I list listeners with ss -tulnp and flag anything that isn’t on my baseline.” An unexpected listening
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What this card says
Short answer
Use ss -tulnp and compare the result to a known baseline.
Example
On a lab web server you expect sshd and the web service, not a strange high port.
Say it in the interview
“I list listeners with ss -tulnp and flag anything that isn’t on my baseline.”
Why it matters
An unexpected listening port is often the first sign of a backdoor.
Learn more in the lesson: 47.3 Linux, Logs and Windows Event IDs