Category Security

Learn how Linux groups control access to files, services, and administrative tools. This guide covers adding users to supplementary groups, assigning multiple groups, changing a primary group, verifying membership, and safely troubleshooting common mistakes.

On Ubuntu, an authorized sudo user can run administrative commands using their own password, rather than sharing the root account password. By default, Ubuntu grants broad sudo permissions to members of the sudo group. The sudoers policy can also define more limited permissions for individual users or groups.

sudo lets an authorized user execute a command as another user, usually root. The sudoers policy determines which commands are permitted and under what conditions. This makes it possible to delegate administrative tasks without sharing the root password.