Nagios XI and Ubuntu returns ‘CHECK_NRPE: Received 0 bytes from daemon’.

When monitoring a remote Ubuntu server which Nagios XI I was receiving the below unknown message for the service status: CHECK_NRPE: Received 0 bytes from daemon. Check the remote server logs for error messages. Following investigation , I noticed the following entry in /var/log/syslog: Nov 11 15:24:58 nrpe[7768]: Error: Request contained command arguments, but argument … More Nagios XI and Ubuntu returns ‘CHECK_NRPE: Received 0 bytes from daemon’.