Why use chroot?
Mainly security. In a couple different ways, first it segments your users from one another. If user X “chmod 777″‘s all his files, he is still protected from user Y. User Y’s scripts are chroot()’d when they run, his ssh or telnet is chroot()’d when he logs in. He can only see and interact with his own mini-environment. This segmentation is not just a positive for user to user problems. It can prevent a single breach from becoming larger. For instance, our troublesome user Y writes a script with a security flaw that allows upload and execution of files. Or perhaps he just installs a faulty script. A malicious client visits user Y’s site and uploads files and executes them, he is running as user Y, and he may be able to damage user Y’s files. However, user X, from the previous example, is still safe, so are our system files that might have allowed privilege escalation. Chroot is not the absolute in security, but I have seen one site get defaced and exploits uploaded that were never able
