Nagios returns: Warning: Return code of 127 for check of service ‘foo’ on host ‘localhost’ was out of bounds.

My home servers were being flagged as down with the warnings below. Turns out my /usr/lib64/nagios/plugins/ directory got corrupted during an rsync. The easy fix was to reinstall the nagios-plugins rpm:

yum reinstall nagios-plugins

Wish all issues were this simple.

 [1236830775] Warning: Return code of 127 for check of service 'PING' on host 'localhost' was out of bounds. Make sure the plugin you're trying to run actually exists.  [1236830815] Warning: Return code of 127 for check of service 'Root Partition' on host 'localhost' was out of bounds. Make sure the plugin you're trying to run actually exists.  [1236830855] Warning: Return code of 127 for check of service 'SSH' on host 'localhost' was out of bounds. Make sure the plugin you're trying to run actually exists.  [1236830895] Warning: Return code of 127 for check of service 'Swap Usage' on host 'localhost' was out of bounds. Make sure the plugin you're trying to run actually exists.  [1236830925] Warning: Return code of 127 for check of service 'Total Processes' on host 'localhost' was out of bounds. Make sure the plugin you're trying to run actually exists.  [1236830965] Warning: Return code of 127 for check of service 'Current Load' on host 'localhost' was out of bounds. Make sure the plugin you're trying to run actually exists.  [1236830975] Warning: Return code of 127 for check of host 'localhost' was out of bounds. Make sure the plugin you're trying to run actually exists.  [1236831005] Warning: Return code of 127 for check of service 'Current Users' on host 'localhost' was out of bounds. Make sure the plugin you're trying to run actually exists.  [1236831045] Warning: Return code of 127 for check of service 'HTTP' on host 'localhost' was out of bounds. Make sure the plugin you're trying to run actually exists.