When a new user is added, where does his user ID gets stored?

The correct answer is E. /etc/passwd. See the full explanation below for the reasoning.

Question

When a new user is added, where does his user ID gets stored?

Options

A/etc/users
B/etc/realm
C/etc/pass
D/etc/shpasswd
E/etc/passwd

How the community answered

(29 responses)

A
3% (1)
B
10% (3)
C
3% (1)
D
3% (1)
E
79% (23)

Community Discussion

Ingrid P.Jun 16, 2026

The correct answer is E, /etc/passwd. This file is the canonical store for local user account information on Linux and Unix systems, and every new user created with useradd or adduser gets a new entry written there. Each line holds seven colon-separated fields: username, password placeholder (the x tells you the actual hash lives in /etc/shadow), UID, GID, GECOS comment, home directory, and login shell. The other options are all fabricated paths, none of them exist as standard Linux files, which makes this a good card to pair with a fill-in-the-blank on the field order so you remember the full structure, not just the filename.

Toby R.Jun 12, 2026

E is right, /etc/passwd is where the user ID (UID) and other account info like the username, home directory, and default shell get stored as a colon-separated entry the moment you run useradd. The other options are made up, none of them exist on a real Linux system.

Anjali D.Jun 22, 2026

E is right, though D trips people up since /etc/shadow is real.

Nina C.Jun 23, 2026

Right, and what helped it click for me is remembering that /etc/shadow exists specifically because /etc/passwd has to be world-readable, so they had to move the hashes somewhere only root can touch.

Nina C.Jun 26, 2026

Got this exact one on my practice run last week and almost second-guessed myself because I kept mixing up the file name with "password" thinking it was only for passwords, but my study group reminded me that /etc/passwd is the whole user account database, UID included. Once that clicked I never missed it again.

Ingrid P.Jun 28, 2026

The UID-to-username mapping is the part worth drilling separately on a card, because the exam loves to test whether you know field order in that colon-delimited structure, not just which file it lives in.

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