I wanted to create an account in my backup machine for a good friend of mine.
As laziness is a fundamental virtue I wanted to avoid as much work as possible, including the part of calling my good friend to tell him to change the password that was random generated in the second machine.
mi first try was:
(as root)
grep <user> /etc/{passwd,shadow,group} >> user_info.text
Then, copy each line of users_info.text into the passwd, shadow and group file in /etc/ on the second unit