Several actions performed by users are recorded by Interchange's usertracking facility, if one is enabled. Usertrack data can actually be obtained from two different locations.

The first location is Interchange itself, where you tune the TrackFile directive to your needs (such as logs/usertrack). This is the approach used in the standard demo.

The second location are the HTTP headers. You can configure the Web server to write this header into access logs; here's an example for the Apache web server:

LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\" \
			%T %v \"%{X-Track}o\"" track
CustomLog /var/log/apache/track.log track