Several times administrating servers you need to create a new user for doing tasks that need to be done by external entities.
Usually when you create a new server, you get root access, or admin access enought to login and to install and configure stuff.
Is not a good Practice to start giving administrative access to external entities, so this is a way of creating a new user, set a password and allow him to log in.
As root or admin user we create a new user
The system it’s gonna ask you the password, name and some other fields, then we switch to the user that we just created:
sudo su - <user-name>
As root, make sure in the sshd_config file the line to allow ssh auth with password is set to “yes”
# Change to no to disable tunnelled clear text passwords PasswordAuthentication yes
Then restart the ssh daemon
service ssh restart