Security-Enhanced Linux (SELinux) is a Linux feature that provides a mechanism for supporting access control security policies, through the use of Linux Security Modules (LSM) in the Linux kernel. It is a set of Kernel modifications and user-space tools that can be added to various Linux distributions. Its architecture strives to separate enforcement of security decisions from the security policy itself and streamlines the volume of software charged with security policy enforcement .
Howto- Disable SELinux on Fedora/Centos/RHEL/SL
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performance of the native 
and other types of servers by using words and number instead of IP addresses. Without DNS servers users visiting a website would have to connect using its IP address (say for example http://88.192.77.211 instead of http://www.unixmen.org). It can be somewhat hard for people to remember IPv4 addresses this becomes even more apparent with many web servers switching to IPv6. I don’t know many people that could easily remember a 32 digit address of each website they visit.
are the full notes on RHEL 5.7 release.
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