groupadd

Additional Notes

groupadd creates a local group. Groups are used to share permissions between users and services.

After creating a group, add users with usermod -aG group user or manage membership with tools such as gpasswd.

Syntax

groupadd [options] group

Parameters

• options: Flags that change how groupadd behaves.
• user: User account affected by the command.
• group: Group account affected by the command.
• file: File or directory whose ownership, mode, or access policy is being changed.

Common Options

• -g GID: Set numeric group ID.
• -r: Create a system group.
• -f: Exit successfully if the group already exists.

Examples

sudo groupadd developers

Create a group.

sudo groupadd -g 2000 lab

Create a group with a specific GID.

sudo usermod -aG developers rani

Add a user to the group.

getent group developers

Check group information.

Practical Notes

• Group membership often requires logging out and back in.
• Use groups to avoid giving broad permissions to everyone.
• System groups are usually for services.
• Check /etc/group or getent group to inspect local/group database entries.