You may need to modify the default commands so that you are using settings that fit your goals in monitoring a Linux box.
On the target box open up the nrpe.cfg file and edit the configuration for the check_users. Here is the default setting, modify the “-w 5” and set it to “-w 1” so that you will get a warning when one user is logged in. Save your changes and watch the Nagios monitor the target box.
command[check_users]=/usr/lib/nagios/plugins/check_users -w 5 -c 10
Here you can see on the Nagios server the default is a warning at 5 and critical is 10 users.
Change the User Numbers
Once the settings are changed the Nagios server should pick that up.
Here you can see that the basic settings have changed and are reflected in the outcome.