How to add/remove user accounts in Ubuntu from a remote machine

Adding a user

To add a user account, use the following syntax, and follow the prompts to give the account a password and identifiable characteristics such as a full name, phone number, etc.

sudo adduser {username}

Deleting a user

To delete a user account and its primary group, use the following syntax:

sudo deluser {username}

Deleting an account does not remove their respective home folder. It is up to you whether or not you wish to delete the folder manually or keep it according to your desired retention policies.

Remember, any user added later on with the same UID/GID as the previous owner will now have access to this folder if you have not taken the necessary precautions.

Backup an existing account

You may want to change these UID/GID values to something more appropriate, such as the root account, and perhaps even relocate the folder to avoid future conflicts:

sudo chown -R root:root /home/{username}/
sudo mkdir /home/archived_users/
sudo mv /home/{username} /home/archived_users/

Lock and Unlock an account

To temporarily lock or unlock a user account, use the following syntax, respectively:

 sudo passwd -l {username}
 sudo passwd -u {username}

Groups

To add or delete a personalized group, use the following syntax, respectively:

sudo addgroup {groupname}
sudo delgroup {groupname}

To add a user to a group, use the following syntax:

sudo adduser {username} {groupname}

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