When CageFS is installed on a cPanel server, it works in conjunction with CloudLinux to provide virtualized environments for users. This means that each user's environment is isolated from other users, enhancing security and stability.

One side effect of CageFS installation is that it can change the shell from jail shell to regular bash for users. This is because CageFS provides its own virtualized environment, which includes the ability to run regular bash.

Here's why this happens:

1. CageFS Environment:

   • CageFS creates a virtualized environment for users, allowing them to run processes within a chrooted environment. This means that the user sees only their own files and processes, enhancing security and stability.

2. jail shell vs. bash:

   • jailshell is a limited shell provided by cPanel. It restricts users to their home directory and prevents them from accessing system files or executing potentially harmful commands.
   • When CageFS is enabled, users are still restricted to their home directories, but they have access to a broader set of commands and utilities provided by the virtualized environment, which includes bash.

3. Enhanced Functionality:

   • By providing users with bash in the CageFS environment, they have access to a wider range of tools and commands, which can be beneficial for development, debugging, and various tasks.

4. Maintaining Compatibility:

   • Offering bash ensures that users can run scripts and commands that may not be supported in jailshell.

5. Security Considerations:

   • While bash provides more functionality, it's important for administrators to carefully manage user permissions and ensure that users are not able to run commands that could potentially compromise the server.

If you want to restrict a user back to jailshell after installing CageFS, you can do so through the cPanel interface or by modifying the user's shell in the /etc/passwd file.

Remember that making changes to user shells can impact their ability to perform certain tasks, so it's essential to communicate any changes with users and ensure that they have the necessary tools and permissions to carry out their tasks.