Linux · User & Group Administration

In a PAM stack, what is the difference between a requisite and a required control keyword when a module fails — and why does the distinction matter for security?

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More in User & Group Administration

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During a standard Debian install you can just press Next past the root password screen, leaving it blank. What does Debian silently do to the first user account as a result?

You have shell access on a fresh Debian box and need to run admin commands. How you enter admin mode depends on one earlier install choice — what determines whether you use sudo -s versus su -l?

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Debian gives you both adduser and useradd, and so does Fedora — but a script that works on Debian's adduser can misbehave on Fedora. Why?

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