monitor log command is cluttered with log entries from sudo, it reads /var/log/messages.
To reduce the noise in this logfile split out the sudo log messages to /var/log/auth.log which was somehow designed for this logging traffic.
Mar 1 09:44:54 LR1 sudo: pam_unix(sudo:session): session opened for user root by cpo(uid=0) Mar 1 09:44:54 LR1 sudo: pam_unix(sudo:session): session closed for user root Mar 1 09:44:54 LR1 sudo: pam_unix(sudo:session): session opened for user root by cpo(uid=0) Mar 1 09:44:54 LR1 sudo: pam_unix(sudo:session): session closed for user root