There is no automated way of doing that. You'd have to extract that information from the log files localhost_access* under $SPECROOT/tomcat/logs.
Build some small scripts that pass to each file and get username and their last login timestamp. It should not be such a big endeavor, considering that you aim for last 30 days. The files are rotated on a daily basis.
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Cătălin Fărcășanu
Senior Consultant
SolvIT Networks
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