Mastering Ubuntu Server - Second Edition

Understanding the /etc/passwd and /etc/shadow files

Now that we know how to create (and delete) user accounts on our server, we are well on our way to being able to manage our users. But where exactly is this information stored? We know that users store their personal files in /home, but is there some kind of database somewhere that keeps track of which user accounts are on our system? Actually, user account information is stored in two special text files:

• /etc/passwd
• /etc/shadow

You can display the contents of each of those two files with the following commands. Take note that any user can look at the contents of /etc/passwd, while only root has access to /etc/shadow:

cat /etc/passwd 
sudo cat /etc/shadow

Go ahead and take a look at these ...