Linux Audit Framework 101 – Basic Rules for Configuration

The Linux audit framework is a very powerful tool to monitor files, directories and system calls. It helps with troubleshooting, accounting and intrusion detection.

Summary of Linux Audit Framework 101 – Basic Rules for Configuration

Starting with Linux auditing can be overwhelming. Fortunately, there is a great feature in the Linux kernel to watch events and log them for us. To give you a quick start to use the Linux Audit Framework, we have collected some basic rules for configuring the audit daemon and its rules. Main Configuration By default the configuration values in /etc/audit/audit.conf are suitable for most systems. If you know your system is very low or very high (e.

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Logging root actions by capturing execve system calls

Logging all actions performed by root might be needed for compliance or security. With the help of Linux audit we log all root actions easy in an audit log.

Summary of Logging root actions by capturing execve system calls

Capturing execve system calls and store them in the audit log For compliance or security reasons you might want to capture all commands executed by the root user. Fortunately enough the Linux audit framework helps with capturing the right system calls and log it to the audit file. Configure audit To enable auditing, use the following commands: # auditctl -a exit,always -F arch=b64 -F euid=0 -S execve -k root-commands # auditctl -a exit,always -F arch=b32 -F euid=0 -S execve -k root-commands These commands will enable monitoring for the execve system call and log it when the effective user ID is 0, equal to the root user.

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Tuning auditd: high-performance Linux Auditing

To achieve better performance with a auditd configuration, it needs to be tuned. See performance boosters like events exclusion, rule ordering, and more.

Summary of Tuning auditd: high-performance Linux Auditing

The Linux Audit framework is a powerful tool to audit system events. From running executables up to system calls, everything can be logged. However, all this audit logging comes at the price of decreased system performance. Let’s have a look at how we can optimize our audit rules. Performance tips Good auditd performance will reduce stress on the Linux kernel and lower its impact. Before changing anything to your system, we suggest benchmarking your system performance before and after.

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