Historically, OP5 has compiled and packaged the NRPE agent for a large number of Linux distributions, but as per Q2 2014 we stopped doing this since it required a lot of maintenance and time. More information on this decision can be found here: https://www.op5.com/blog/blogs/op5-developers-blog/deprecation-notices-q2-2014/
Note that this article is intended for Debian 6, 7, 8 and Ubuntu 16.04 client hosts, and that these steps never should be performed on an OP5 Monitor server.
1. Install the NRPE package together with plugins:
# apt-get install nagios-nrpe-server nagios-plugins-basic
2. Create a new file called /etc/nagios/nrpe.d/op5_commands.cfg containing the following information:
These paths to the plugins should match the paths to the installed plugins in step 1.
3. Now edit /etc/nagios/nrpe.cfg and add your Monitor server(s) address(es) to the allowed_hosts parameter as a comma-separated list in the appropriate section:
4. Restart the nrpe agent on the host:
# /etc/init.d/nagios-nrpe-server restart
Now you can add the services via the function "Add UNIX client services" when adding a host in op5 Monitor.
If the host is behind a firewall, or you have enabled firewall software on the host, you need to open for incoming traffic on TCP port 5666.