User and Group

Update USER and GROUP with real value.

Create User

CentOS and Ubuntu

USER=username
sudo useradd $USER
sudo usermod -aG wheel $USER

USER=username
PASSWORD=password
useradd -m -s /bin/bash -p $(openssl passwd -1 $PASSWORD) $USER
usermod -aG sudo $USER

Ubuntu

USER=username
sudo adduser --gecos "" $USER
sudo usermod -aG sudo $USER

USER=username
PASSWORD=password
useradd -m -s /bin/bash -p $(openssl passwd -1 $PASSWORD) $USER
usermod -aG sudo $USER

Password less sudo command execution

USER=username
sudo tee -a /etc/sudoers.d/$USER << EOF
$USER ALL=(ALL) NOPASSWD: ALL
EOF

Sometimes user needs to logout and re-login to update the group. Or follow this to reload users groups without logging out.

logout

Create Group

CentOS and Ubuntu

sudo groupadd GROUP

Ubuntu

sudo addgroup GROUP

Update User

Add users to group

sudo usermod -aG GROUP USER

sudo gpasswd -a USER GROUP

Update user password

sudo passwd USER

Remove user from a group

sudo gpasswd -d USER GROUP

Update user default shell

sudo usermod -s /bin/bash USER

sudo usermod -s /usr/sbin/nologin USER

Delete password

sudo passwd -d USER

Delete User

CentOS and Ubuntu

sudo userdel USER

Ubuntu

sudo deluser USER

Delete user files

sudo rm /home/USER -rf

Delete Group

CentOS and Ubuntu

sudo groupdel GROUP

Ubuntu

sudo delgroup GROUP