InformationMonitor session initiation events. The parameters in this section track changes to the files associated with session events. The file /var/run/utmp tracks all currently logged in users. All audit records will be tagged with the identifier 'session.' The /var/log/wtmp file tracks logins, logouts, shutdown, and reboot events. 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.'
The last command can be used to read /var/log/wtmp (last with no parameters) and /var/run/utmp (last -f /var/run/utmp)
Reloading the auditd config to set active settings requires the auditd service to be restarted, and may require a system reboot.
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).
SolutionEdit or create a file in the /etc/audit/rules.d/ directory ending in .rules
Example: vi /etc/audit/rules.d/50-session.rules
Add the following lines:
-w /var/run/utmp -p wa -k session
-w /var/log/wtmp -p wa -k logins
-w /var/log/btmp -p wa -k logins