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...

Creating and removing users in Ubuntu Linux

Creating users in Ubuntu can be done with one of two commands: adduser and useradd. This can be a little confusing at first, because both of these commands do the same thing (in different ways) and are named very similarly. I’ll go over the useradd command first and...

Understanding users and groups in Linux

When it comes to a server, users are essential—without users to serve, then there’s no real need for a server in the first place. The subject of user management itself within the world of IT is in and of itself quite vast. Entire books have been written on particular...

Setting up public key authentication in Linux

In this tutorial, I will show how to set up secure public key authentication. Getting ready You might need root privileges for certain tasks. How to do it… Follow these steps to set up public key authentication: Add a new user. You can skip this step if you have...