Auditd gives you the ability to write your own custom audit rules. This functionality allows an administrator to keep a close eye on system calls, file access, and user behavior. This added functionality is especially useful in environments that are requred to adhear to compliance standards that are above and beyond normal standards. Think PCI.
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RHEL6 – Simple Iptables How To
Your mother and I were talking last night about how important it is to properly configure Iptables, and how despite that fact, many just choose to disable it. So today we are going to discuss iptables.