Monitor session initiation events. The parameters in this section track changes to the files associated with session events. The file /var/run/utmp file tracks all currently logged in users. The /var/log/wtmp file tracks logins, logouts, shutdown and reboot events. All audit records will be tagged with the identifier "session." The file /var/log/btmp keeps track of failed login attempts and can be read by entering the command /usr/bin/last -f /var/log/btmp. All audit records will be tagged with the identifier "logins." Monitoring these files for changes could alert a system administrator to logins occurring at unusual hours, which could indicate intruder activity (i.e. a user logging in at a time when they do not normally log in).