Monitoring Linux firewalls with firelogd
Having a firewall is important for overall security, but it's equally important to regularly monitor its logs.
Log monitoring helps you track possible access problems, provides data on the effectiveness of your rule sets, and documents hack attempts.
Monitoring such activity provides an excellent means to check out what's hitting your server and fix problems before they get out of hand. However, firewall logs tend to contain verbose network information in as compact a message as possible, which can be rather tedious to sift through.
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