Increasing Parallels H-Sphere Security - RedHat Linux   The following steps should increase the level of security of your Parallels H-Sphere Servers. The guidelines we’ve made public below for the Parallels H-Sphere community include about 60% of our complete server hardening package. If you need more complete protection customized to the needs of your server or server cluster, please call us toll free at 1-888-887-6727 1-717-484-1062 for international clients) or email us at to speak with a solutions consultant today!” Please keep in mind security is a way of life and a life style. It is a set of procedures and policies that must be malleable, and yet followed consistently. There is no such thing as a one time hardening just like there is no such thing as a one time anti-virus install. As new threats or attacks arise, it’s important that you never allow yourself to feel too safe or too secure, always check things out, always be open to learning new security philosophies, and always be on the look out for suspicious activity on your machines. IMPORTANT NOTE:  This document is based on CentOS, RedHat Linux 7.3 and Enterprise.  The concepts should be similar across operating systems, but the commands will very likely be different.  Also, never assume the directory structures exist in your system as written in the document.  Never blindly follow security instructions -- read, review, compare, apply as it fits your system. Install patches as necessary; do on a regular basis Disable telnet Do an initial hardening of the operating system Remove regular user and world access from c compilers Secure host.conf Install chkrootkit, and set up in cron Install root kit hunter, and set up in cron Install rootcheck, and set up in cron Install logwatch Disable direct root login Only allow certain IP's access to SSH Install a firewall Recreate the /tmp directory on its own partition Secure shared memory Remove unnecessary packages Set PHP up for safe mode on Turn off server signatures If you are going to grant shell access in a shared environment What if I have to regenerate the SSH Key? Change your passwords on a regular basis Daily routine Also see System Administrator Resources IMPORTANT NOTE:  This document and all linked document is being provided as a good will gesture to the Parallels H-Sphere community and to others who may benefit from its use.  Dynamic Net, Inc. makes no representations implied or explicit as to their value or warranty. Dynamic Net, Inc. will not be held liable for any damage resulting in the application of the steps and procedures noted.  If you feel uncomfortable at all about doing any of the steps, make a complete system backup and hire a third party like We Manage Servers to do the work for you.  We Manage Servers is a division of Dynamic Net, Inc.