NRPE - No Output Returned From Plugin

Problem Description

This KB article addresses the following NRPE error:

No Output Returned From Plugin

Assumed Knowledge

The following KB article contains an explanation of how NRPE works and may need to be referenced to completely understand the problem and solution that is provided here:

NRPE - Agent and Plugin Explained

Troubleshooting The Error

There are multiple solutions to this problem depending on the cause.

Permissions

The most common solution is to check the permissions on the check_nrpe binary on the Nagios XI server:

ls -la /usr/local/nagios/libexec/check_nrpe

The expected permissions should resemble:

-rwxrwxr-x. 1 nagios nagios  75444 Nov 21 01:38 check_nrpe

If not, change ownership to user/group "nagios" and fix up the permissions:

chown nagios:nagios /usr/local/nagios/libexec/check_nrpe
chmod u+rwx /usr/local/nagios/libexec/check_nrpe
chmod u+rx /usr/local/nagios/libexec/check_nrpe

Missing Plugin

Another cause is a missing plugin file, though, in order to receive this error, you usually have to also be experiencing a secondary configuration issue. In order to resolve issues relating to missing plugins, please refer to the following KB article:

NRPE - Return Code Of 127 Is Out Of Bounds - Plugin May Be Missing

Mismatch of Arguments between Nagios XI and nrpe.cfg

The final cause, and usually the secondary issue for those who found their plugin missing from the expected location, is an argument usage mismatch between the remote host's nrpe.cfg command directive and the arguments passed by Nagios XI through check_nrpe.   Please refer to the following KB article to help troubleshoot this:

NRPE - CHECK_NRPE: Received 0 Bytes From Daemon. Check The Remote Server Logs For Error Messages

Final Thoughts

For any support related questions please visit the Nagios Support Forums at:

http://support.nagios.com/forum/