How do I read an Apache log? [closed]

Question

I see lines like this in my apache usage log, but don't understand how to read them:

123.16.65.84 - - [04/Nov/2011:00:30:09 +0000] "GET /media/product/3596_5084_120.jpg HTTP/1.1" 304 175 "http://www.audaaai.com/loa-hi-fi_dm13.html&brand=36" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; GTB7.1; .NET CLR 2.0.50727; AskTbMPC2/5.11.0.15286)"

How can I understand these lines?

Answer 1

• 123.16.65.84 is the IP-address of the client.
• The first hyphen would contain the client-identifier from identd, but a hyphen is in its place as that information is unavailable.
• The second hyphen would contain the users username, if the user were authenticated by http.
• [04/Nov/2011:00:30:09 +0000] is the time of the request.
• GET is the request method
• /media/product/3596_5084_120.jpg is the request URI
• HTTP/1.1 is the protocol and version
• 304 is the returned status code. (304 means 'Not Modified')
• 175 is the amount of bytes in the returned body.
• http://www.audaaai.com/loa-hi-fi_dm13.html&brand=36 is the referer-URL
• Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; GTB7.1; .NET CLR 2.0.50727; AskTbMPC2/5.11.0.15286) is the user agent / browser used by the client.

Check out http://httpd.apache.org/docs/1.3/logs.html#common for a more thorough explanation.