check_users is used to monitor the number of logged-in users:
user@linux:nagios/libexec$ ./check_users -w 5 -c 10 USERS CRITICAL - 20 users currently logged in |users=20;5;10;0
It has just two options:
This is the threshold for the number of logged-in users after which the plugin should give a warning.
This is the threshold for a critical state, measured by the number of logged-in users.
The performance data after the
| is as usual visible only on the command line; Nagios does not include it in the Web interface.