linux 用户 配置

1. Add a new User

1 # add a new user
2 sudo adduser username

3 # add a new user to a group
4 sudo adduser username groupname

5 # add a new user foo to the group www-data
6 useradd -g www-data foo

https://superuser.com/questions/624745/ubuntu-server-create-group-create-user-user-specific-access

https://linuxhint.com/difference-between-useradd-adduser/

https://www.cyberciti.biz/faq/ubuntu-add-user-to-group-www-data/

Create a group

1 sudo addgroup groupname

2. Modify existing user

2.1 Change folder owner

chown restricted_user:group /restricted/directory
chmod 755 /restricted/directory

https://superuser.com/questions/149404/create-an-ssh-user-who-only-has-permission-to-access-specific-folders

https://askubuntu.com/questions/402980/give-user-write-access-to-folder

2.2 Adding an existing user to group

Add an existing user bar to Apache’s www-data group on Ubuntu using usermod -a -G www-data bar command.

2.3 Check the group a user is in 

1 groups [username]
2 id [username]