O’Reilly Network: Log Rhythms

“Logs are the pulse of your web server — the rhythms produced
by the comings and goings of your visitors. In this column I’ll
give you a gentle introduction to Apache web server logs and their
place in monitoring, security, marketing, and feedback.

“Before you go running for the hills, I won’t be talking about
those mathematical logarithms that gave you a headache in high
school. Your web server records visits to your web site in the form
of logs, a text file (or files) containing entries corresponding to
each request (or “hit”). At first glance, logs may look convoluted,
but they’re actually quite simple. Once you’re familiar with the
notation, you’ll be reading your logs as easily as your daily

“Let’s see what’s lurking inside that log. For the purposes of
this look at a typical set of logs, I’m assuming your Apache server
has been configured to use Common Log Format (CLF), the default in
a fresh Apache installation. Your httpd.conf file should contain
the following configuration directive….”

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