I'm trying to configure a service check via NRPE and having some difficulty. From the monitoring server, I can successfully execute NRPE via CLI: [root@mon01 etc]# /usr/local/nagios/libexec/check_nrpe -H 10.140.122.51 -c check_prov FILE_AGE OK: /var/log/prov.log is 4 seconds old and 8033817 bytes All my hosts are in /usr/local/nagios/etc/hosts, with service_checks defined in them. I defined this NRPE check as: define service{ use generic-service host_name servername.serverdomain service_description check_prov is_volatile 0 check_period 24x7 max_check_attempts 3 normal_check_interval 3 retry_check_interval 1 notification_interval 120 notification_period 24x7 notification_options w,u,c,r check_command check_nrpe!check_prov } within nagios.cfg, I have a commands.cfg file defined: cfg_file=/usr/local/nagios/etc/objects/commands.cfg within commands.cfg: # 'check_ccprov' command definition define command{ command_name check_prov command_line $USER1$/check_nrpe -H $HOSTADDRESS -c check_prov } Nagios is giving me an error: Checking services... Error: Service check command 'check_nrpe' specified in service 'check_ccprov' for host 'servername.serverdomain' not defined anywhere! But it is defined?! From the documentation the check_command should be "check_nrpe!$service" within service definition? Thanks!