Brian, First thing to check is version of NRPE? NRPE comes with two version, stripped and non-stripped. Make sure both machine has the same version running. If not, then play with the "-n" option to fix the incompatibility issues. Then check if your nrpe.cfg where you define the actual checks are the same on both nagios server and the monitored machine. I hope this helps. <div class="gmail_quote">On Fri, Apr 17, 2009 at 12:54 PM, Marc Ismael <<a href="mailto:marcismael@gmail.com">marcismael@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> <div class="gmail_quote"><div class="im">On Fri, Apr 17, 2009 at 11:39 PM, Brian O'Mahony <<a href="mailto:brian.omahony@curamsoftware.com" target="_blank">brian.omahony@curamsoftware.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> <div link="blue" vlink="purple" lang="EN-US"> <div> There seems to be a lot of documentation on Nagios all over the web. I must say im impressed with it, even though im still installing it. Basically I have the server set up and monitoring itself, and I have one remote machine, which I have set up 6 tests on just for testing. I have the nagios plugins and nrpe installed and everything is working in that regard. If I run the check_nrpe command with any of the base remote commands in the /etc/nagios/nrpe.cfg file, I get the output to my screen. [nagios@mido ~]$ /usr/lib/nagios/plugins/check_nrpe -H 172.16.165.248 -c check_root_disk DISK OK - free space: / 4460 MB (95% inode=98%);| /=208MB;4898;4908;0;4918 (IP is the remote machine) However when these tests are added to server.cfg files, I get Status==UNKNOWN and Status Information=(No output returned from plugin) I reckon its something simple that ive missed, but ive gotten a bit lost looking for it. Server: Rhel5.1 Nagios-3.0.6 installed from source Plugins 1.4.13-4 from rpm Plugins-nrpe 2.12-6 from rpm Remote Server: Rhel4u6 nagios-nrpe-2.5.2-1 nagios-plugins-nrpe-2.12-6 nagios-plugins-1.4.13-1.el4 Thanks B</div></div></blockquote></div><div> i would do the following - make sure that nrpe on the nagios server is connecting to the correct port at the nrpe server by comparing nrpe config files. (check encryption, port, privs, etc). - make sure that nrpe service on the clients are actually running and listening on the configured port. - check service and command definitions Also I would double check the nrpe pdf documentation -- there are examples there to get you up and running with nrpe. </div></div> ------------------------------------------------------------------------------ Stay on top of everything new and different, both inside and around Java (TM) technology - register by April 22, and save $200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco. 300 plus technical and hands-on sessions. Register today. Use priority code J9JMT32. <a href="http://p.sf.net/sfu/p" target="_blank">http://p.sf.net/sfu/p</a> _______________________________________________ Nagios-users mailing list <a href="mailto:Nagios-users@lists.sourceforge.net">Nagios-users@lists.sourceforge.net</a> <a href="https://lists.sourceforge.net/lists/listinfo/nagios-users" target="_blank">https://lists.sourceforge.net/lists/listinfo/nagios-users</a> ::: Please include Nagios version, plugin version (-v) and OS when reporting any issue. ::: Messages without supporting info will risk being sent to /dev/null </blockquote></div> -- Cordially, Shadhin Rahman