Users

User Account Files

• /etc/passwd – Stores user account details.
• /etc/shadow – Stores encrypted passwords and authentication data.

Creating Users

• Do not edit files manually – high risk of login failures.
• Use useradd to safely create users.
• useradd automatically updates /etc/passwd and /etc/shadow.

Why Use `useradd

• Prevents syntax and permission errors.
• Ensures consistent and secure account creation.

Before Adding Users

• Check default settings used by useradd.
• Defaults are defined in configuration files.
• Proper defaults reduce post-creation fixes.

Key Configuration Files

File	Purpose
/etc/login.defs	Default UID, GID, password policies
/etc/default/useradd	Default home directory, shell, groups

Remember : Verify useradd defaults before creating users to avoid reconfiguration later.