Adding Existing Linux User to Group
To add an existing Linux user to a specified group, use the usermod command with root privileges.
Steps to Add User to Group
- Step 1: Access a terminal with sudo or root access.
- Step 2: Execute the command: usermod -aG groupname username
- -a: Append to avoid removing existing groups.
- -G: Specify the group name.
- groupname: Replace with the target group.
- username: Replace with the existing user.
- Step 3: Confirm changes using groups username or id username to display assigned groups.
Important Considerations
Permissions: The command requires root privileges; use sudo if not root. Example: sudo usermod -aG groupname username.
Append Option: Always include -a to preserve current group memberships; omission may revoke other group access.
Login Update: Changes apply after the user logs out and back in.
Verifying Group Membership
Run groups username to list current groups. Verify the output includes the newly added group.
