Physical and Environmental Considerations

The location and physical security of a server system is one of the first things to consider when putting a system online.  Your needs may not dictate that your server be in a secure Tier 4 co-location facility, but your servers may need to be at least in a locked and controlled access room in the back corner of your office suite.  The bottom line is that you can't certify a system secure if it is in common access kitchen that you share with 4 other businesses.

System hardening is the application of known best practices and security measures in order to increase the security resilience of a network. 

The fundamental philosophy of system hardening is to reduce the overall exposure to risk by reducing the attack surface area. 

Harden Linux systems

*There are many distributions of Linux, our guide covers most standard Debian, RedHat, CentOS and BSD versions, however your particular distribution of Linux may use different default paths and system configuration files.