Ubuntu Users and Groups Management

Those are commands which you can use to manage Ubuntu Users and Groups

User Commands
passwd Change own password
whoami Who am I?

Sudo command
sudo -i Elevate permission and log in as the root account
sudo adduser username sudo Add a user to the sudo group:
sudo getent group sudo Check members of sudo group

User Management
cut -d: -f1 /etc/passwd List Users
sudo adduser new_username Add a new user you can use:
sudo userdel username Remove/delete user
sudo rm -r /home/username Delete the home directory for the deleted user account
usermod -l new_username old_username Modify the username of a user:
sudo passwd username Change the password for a user:
sudo chsh username Change the shell for a user:
sudo chfn username Change the details for a user (for example real name):
sudo adduser username sudo Add a user to the sudo group:

Enable Root User
sudo nano /etc/passwd
sudo nano /etc/shadow
The character “x” represents a blank or empty password.
The character “!” represents that password is locked.
sudo passwd root
sudo passwd -u root
To unlock the account. This should return
passwd: password expiry information changed

Change this as well
sudo nano /etc/ssh/sshd_config
PermitRootLogin prohibit-password change to
PermitRootLogin yes
sudo service ssh restart

Change the root password in Ubuntu
Type the following command to become a root user and issue passwd:
sudo passwd root
Test it with your root password by typing the following command:
sudo -i
su –

Groups
sudo groups List Groups
sudo groups wpk Get groups where user wpk is a member