Every firewall comes with built-in reporting tools that provide details about your traffic. Another firewall rules best practice is to audit those logs regularly to look for changes or anomalies that might suggest modifications to your firewall settings.
This log data will be a critical source of information about which firewall rules are being invoked most frequently — and which aren’t ever being used at all. Both types of information are critical for optimizing your firewall.
Log data can also help you find “false positives,” traffic that shouldn’t trigger security rules but is doing so any way. Changing your firewall rules may help you cut down on these false positives and improve service to end users.
If you have a particularly large or active network, you may find that you need additional log analysis tools beyond those provided by the firewall manufacturer to make sense of your log data. Some of the most advanced tools include artificial intelligence or machine learning capabilities that can help you spot important details that you might otherwise have missed.