Thanks murrant and laf. Greatly appreciated.
I followed steps on doc Home - LibreNMS Docs and installed Nagios plugins on LibreNMS server.
After checking the argument options, configured a test service check on a remote server ‘report’ with IP 172.16.9.76:
the error message on LibreNMS
Looks like that LibreNMS requires login credentials to the OS in additional to login credentials to MySQL.
Any where I can configure login credentials to the OS of the remote server on LibreNMS?
Any help would be greatly appreciated.