List a user's group memberships with groups

Check which groups grant a user their sudo, docker, or file permissions — the first diagnostic for 'permission denied'.

LinuxgroupspermissionsLow risk

Run `groups alice` (or bare `groups` for yourself) to print every group the account belongs to.

01Command

Command

$ groups alice

02What it does

Most file and capability access on Linux is granted through group membership — wheel/sudo for root, docker for the daemon socket, www-data for web trees. `groups user` resolves those memberships through NSS, so it also works for domain users. Two gotchas: memberships added with usermod only apply to new login sessions, so `newgrp docker` or re-login is needed, and the comma-joined member list shown by `getent group docker` omits members whose primary group it is.

03Risk

RiskLow risk

Requirementscoreutils

04Undo

✓No undo needed — this command does not change persistent state.

05Sources

groups(1) — print group memberships a user is in
man7.org · technical · 2026-09-17
Evidence: Documents groups printing the group names for a specified user, defaulting to the current user.

Last verified: 2026-09-17 · Category: Security & Privacy

06Related solutions

Make a File Immutable with chattr +i

Linuximmutablepermissionschattr

chattr sets filesystem attributes that override normal permissions — +i makes a file unmodifiable and undeletable, even by root.

Medium risk ✓ 2026-09-17