Check_NRPE services all coming back with (No output

[dwhitfield]

We don't have enough info, and at this point, with 1 reported instance, it's not likely a nagios issue. It'll be something we keep an eye out for though for sure.

Wild speculation, but maybe this will give you some things to think about in case you see other weirdness in your environment:
It could be a failed update.
It could be a bad drive, or some sort of temporary radiation on the drive. Possibly some sort of RAM corrupt as well, though that seems less likely.
It could be some sort of configuration script (chef, puppet, ansible) gone awry.
It could be malware or some other sort of infiltration (but NRPE seems a strange target, but again, maybe someone was trying to siphon off NRPE info and somehow messed it up).