A log line records a connection from 192.0.2.25 and you want the PTR record for that address. Type the complete dig command, with no @server and no query options, that performs the reverse lookup.

LPIC-1 Exam 102-500, objective 109. Networking fundamentals easy

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Answer

Type the answer.

Accepted answers

Case sensitive — Linux is, and grading LS as ls would teach a falsehood.

Why

dig -x ADDRESS builds the reverse name for you: 192.0.2.25 becomes 25.2.0.192.in-addr.arpa and the query type is set to PTR. Without -x you would have to reverse the octets and append the in-addr.arpa suffix by hand, and IPv6 addresses would need nibble-reversed labels under ip6.arpa. A missing PTR is a server-side omission: forward and reverse zones are separate, and one does not imply the other.

Where this comes from

Cited
manual page dig(1)

Practise this

Reading one question is not practice. The trainer will draw a short set from objective 109 and space the ones you get wrong.

Practise LPIC-1 Exam 102-500

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