W3C Extended Log File Format (IIS 6.0)

For those of us that work with IIS log files, enjoy the table below. The challenge is to know which fields within the logs will provide you with actionable data. For instance, will knowing the User-Agent string of each visitor to your site help your business? Eric Peterson covers this topic very well in his book, "Web Analytics Demystified." It would also be helpful to understand how to enable/disable specific fields within IIS manager along with the status codes for each server call.

The W3C Extended log file format is the default log file format for IIS. It is a customizable ASCII text-based format. You can use IIS Manager to select which fields to include in the log file, which allows you to keep log files as small as possible. Because HTTP.sys handles the W3C Extended log file format, this format records HTTP.sys kernel-mode cache hits.

Field	Appears As	Description	Default Y/N
Date	date	The date on which the activity occurred.	Y
Time	time	The time, in coordinated universal time (UTC), at which the activity occurred.	Y
Client IP Address	c-ip	The IP address of the client that made the request.	Y
User Name	cs-username	The name of the authenticated user who accessed your server. Anonymous users are indicated by a hyphen.	Y
Service Name and Instance Number	s-sitename	The Internet service name and instance number that was running on the client.	N
Server Name	s-computername	The name of the server on which the log file entry was generated.	N
Server IP Address	s-ip	The IP address of the server on which the log file entry was generated.	Y
Server Port	s-port	The server port number that is configured for the service.	Y
Method	cs-method	The requested action, for example, a GET method.	Y
URI Stem	cs-uri-stem	The target of the action, for example, Default.htm.	Y
URI Query	cs-uri-query	The query, if any, that the client was trying to perform. A Universal Resource Identifier (URI) query is necessary only for dynamic pages.	Y
HTTP Status	sc-status	The HTTP status code.	Y
Win32 Status	sc-win32-status	The Windows status code.	N
Bytes Sent	sc-bytes	The number of bytes that the server sent.	N
Bytes Received	cs-bytes	The number of bytes that the server received.	N
Time Taken	time-taken	The length of time that the action took, in milliseconds.	N
Protocol Version	cs-version	The protocol version —HTTP or FTP —that the client used.	N
Host	cs-host	The host header name, if any.	N
User Agent	cs(User-Agent)	The browser type that the client used.	Y
Cookie	cs(Cookie)	The content of the cookie sent or received, if any.	N
Referrer	cs(Referrer)	The site that the user last visited. This site provided a link to the current site.	N
Protocol Substatus	sc-substatus	The substatus error code.	Y