check-nrpe

[tomskaczmarek]

I am new to the latest version of Nagios Core and the nrpe plugin, but I began using these several years ago (earlier versions) when the information in the UBUNTU server documentation seemed to work. I teach a class where I introduce students to monitoring in UBUNTU. We are currently using UBUBTU 22.04 and I have installed NAGIOS 4.1.11 and nagios plugins 2.2.4 on my Nagios server. I have also added nagios plugins (2.2.4) to a remote server to act as a cleint. Documentation seems to indicate using check_nrpe in the command definition in the client service defintion.

I defined a configuration directory for remote host (/usr/local/nagios/etc/hosts) and I have successfully added a host definition for the client; nagios succefully reports the client is up and running. I added a service 2 definitions to check ssh and disk utilization on the client; the ssh service reports, but disk utilization fails; this is where I have a problem.

There are numerous sites (including Nagios nrpe dpcumentation) that suggest to me that check_nrpe is an executable module that resides in /usr/local/nagios/libexec/. I assume that it gathers up the arguments and sends them to the remote client to execute. I have constructed a command definition in commands.cfg that attempts to invoke this module (check_nrpe) using the command_line attribute with the arguments taken from the service definition; this is based on the nagios pulin documentation. I use this for checking disk utilization on the remote client (check_command check_nrpe!.check_all_disks!<IP address for the remote server/client>). Can someone hlep debug this?

Here are portions of the 2 configuration files:
/usr/local/nagios/etc/objects/commands.cfg
...
define command {
command_name check_nrpe
command_line /usr/local/nagios/libexec/check_nrpe -H $HOSTADDRESS$ -C $ARG1$
}
...

/usr/local/nagios/etc/hosts/<name>
...
define service {
use generic-service
host_name remote
service_description SSH
check_command check_ssh
}

define service {
use generic-service
host_name remote
service_description nrpe disk
check_command check_nrpe!check_all_disks!<ip-address>
}
...

[kg2857]

Is nrpe running on the remote host? It might be running from xinetd or as a service.
Go to your host that's being checked and look in /usr/local/nagios/etc/nrpe.cfg and /usr/local/nagios/etc/nrpe/ for the check_all_disks command.