I have this problem with NRPE, all the stuff I've found so far on the net seems to point me at things I've already tried.

# /usr/local/nagios/plugins/check_nrpe -H nrpeclient

gives

NRPE v2.12

as expected.

Running the command by hand (as defined in nrpe.cfg on "nrpeclient", gives the expected response

nrpe.cfg:

command[check_openmanage]=/usr/lib/nagios/plugins/additional/check_openmanage -s -e   -b ctrl_driver=0 bat_charge

"Expected response"

But if I try to run the command from the Nagios server I get the following:

# /usr/local/nagios/plugins/check_nrpe -H comxps -c check_openmanage
NRPE: Unable to read output

Can anyone think of anywhere else I might have made a mistake with this? I've done the same thing on multiple other servers with no problem. The only difference I can think of with this is that this box is RHEL 5 based, whereas the others are RHEL 4 based.

Those two bits above that I've tested are the what most people seem to suggest when people have had this problem.

I should mention that I get a weird error in the logs when I restart nrpe:

nrpe[14534]: Unable to open config file '/usr/local/nagios/etc/nrpe.cfg' for reading 
nrpe[14534]: Continuing with errors...
nrpe[14535]: Starting up daemon
nrpe[14535]: Warning: Daemon is configured to accept command arguments from clients!
nrpe[14535]: Listening for connections on port 5666 
nrpe[14535]: Allowing connections from: bodbck,combck,nam-bck

Even though, it's plainly reading that /usr/local/nagios/etc/nrpe.cfg file to get the stuff it's talking about further down..