If you need to configure the Security level and firewall of your Red Hat system and you only has a SSH access to the system, use bellow command as a privileged user.
system-config-securitylevel-tui
ssh
Configuring SFTP CHROOT service
Let’s consider a situation where you need to configure a secure FTP service in your Linux server without installing any new packages to the system. Easy way of achieving this scenario is by configuring a SFTP CHROOT service in your Linux system. By Default all Linux systems are pre configured with SSH service. There for you only need to edit the existing configuration for this purpose.
1) Modify “/etc/ssh/sshd_config” file to reflect bellow changes
#Subsystem sftp /usr/lib/openssh/sftp-server
Subsystem sftp internal-sftp