Make sure you have nrpe installed on remote host. Add the new service in /usr/local/nagios/etc/services/my_checks.cfg
1. Example adding of inodes check:
define service{
use generic-service
hostgroup_name monitored-hosts
service_description Check system inodes
check_command check_nrpe!check_disk_inodes
servicegroups sysservices
}
2. On server add the script to /usr/local/nagios/libexec/ directory.
3. Add command to nrpe config /usr/local/nagios/etc/nrpe.cfg
... command[check_disk_inodes]=/usr/local/nagios/libexec/check_disk_inodes ...
4. Reload nagios server and nrpe on remote server.