User Management And Permissions
===============================

https://www.tecmint.com/add-users-in-linux/

https://www.cyberciti.biz/faq/create-a-user-account-on-ubuntu-linux/


.. code-block:: bash

    #create user
    sudo adduser ali --no-create-home --uid 2000 


    #here are all users and groups
    cat /etc/passwd
    cat /etc/group


    #delete user and their private group in one go (with a warning issued)
    sudo deluser ali


    # add user to the sudo group
    usermod -aG sudo mk



    # rename user and group from mk2 to mk
    sudo usermod -l mk mk2
    sudo groupmod -n mk mk2

    # change user id
    sudo usermod -u 1000 mk

    # change group id
    sudo groupmod -g 1000 mk

    # to change the home directory of a logged off user
    sudo usermod -d /home/mk -m mk


    # create a temporary user
    sudo adduser mk2 --uid 3000

    # add certain priveleges
    sudo usermod -aG dialout,tty,docker,root,sudo mk2


    sudo adduser mk
    sudo usermod -aG dialout,tty,docker,root mk
    #you can check all your subscribed groups
    groups mk

    # assign all groups from user ubuntu to user mk
    sudo usermod -aG $(groups ubuntu | sed 's/\s\+/,/g') mk 

    # change user_id
    sudo usermod -u 1000 mk

    # change group id
    sudo groupmod -g 1000 mk

    # query user id and group id
    id -u mk
    id -g mk


    #sudo without typing passwords
    echo "mk     ALL=(ALL) NOPASSWD:ALL" | sudo tee -a /etc/sudoers