There are several reasons to restrict a SSH user session to a particular directory, especially on web servers, but the obvious one is a system security. In order to lock SSH users in a certain directory, we can use chroot mechanism.
change root (chroot) in Unix-like systems such as Linux, is a means of separating specific user operations from the rest of the Linux system; changes the apparent root directory for the current running user process and its child process with new root directory called a chrooted jail.
In this tutorial, we’ll show you how to restrict a SSH user access to a given directory in Linux. Note that we’ll run the all the commands as root, use the sudo command if you are logged into server as a normal user.
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