You inherit a host whose password hashes still sit in the second field of the world-readable /etc/passwd, with no /etc/shadow in place. Type the command from the shadow suite, with no options, that moves those hashes into /etc/shadow and leaves an x behind.
LPIC-1 Exam 102-500, objective 110. Security easy
Machine-checked — no person has signed for it. This question was read against the source cited below by an automated pass, which found no contradiction. That is a weaker claim than it sounds: the same kind of process wrote the question, so it can confirm its own mistake.
Treat it as a good draft rather than as settled fact, and read the source below before you rely on it. It is not used in mock exams here — only questions a person has signed for are.
How these questions are written — where each question comes from, what the verification ledger records, and what happens when one is found wrong.
Answer
Type the answer.
Accepted answers
pwconv/usr/sbin/pwconv
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
pwconv creates or updates /etc/shadow from /etc/passwd, moving each hash out of the world-readable file and replacing it with an x placeholder. Its inverse, pwunconv, writes the hashes back into /etc/passwd and removes /etc/shadow. The group equivalents are grpconv and grpunconv, which handle /etc/gshadow. Shadowing matters because /etc/passwd must stay readable by everyone so that UIDs can be mapped to names, while hashes must not be.
Where this comes from
- Cited
- manual page pwconv(8)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 110 and space the ones you get wrong.
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