Passive Checks and NRDP

• Active Checks:
• Passive Checks:

Configure Passive Checks

• In the main nagios configuration (/usr/local/nagios/etc/nagios.cfg)

accept_passive_service_checks=1
accept_passive_host_checks=1
log_passive_checks=1

• In the host definition

define host {
    use                         generic-host
    host_name                   linuxmachine1
    address                     192.168.0.11
    active_checks_enabled       0
    passive_checks_enabled      1
}

• In the service definition

define service {
    use                         local-service
    host_name                   linuxmachine1
    service_description         diskspace
    active_checks_enabled       0
    passive_checks_enabled      1

}

• Refer Here
• Build a sample script around PROCESS_HOST_CHECK_RESULT to accept hostname, status code and output from check

#!/bin/bash

NOW=`date +%s`
HOST=$1
STATUS=$2
OUTPUT=$3

echo "[$NOW] PROCESS_HOST_CHECK_RESULT;$HOST;$STATUS;$OUTPUT \
     > /var/nagios/rw/nagios.cmd

exit 0

Using NRDP

• NRDP is a technology for sending results to Nagios instance remotely. It provides simple API to send the results to Nagios Instance using HTTP Protocol
• NRDP consists of two parts
  • Server: This part is responsible for receiving check results from remote hosts and passing them to nagios.
  • Client: The client part getts to data be send as commandline arguments it sends it across to server.
• Refer Here

Monitoring Remote Hosts

• For monitoring remote hosts

  • SSH
  • NRPE (Nagios Remote Plugin Executor)

• NRPE is a client-server solution for running check commands on remote computers

• NRPE uses TCP protocol with SSL encryption on top of it. Enabling encryption is optional.

• NRPE communicates on 5666

• NRPE Workflow

• NRPE can be downloaded from Refer Here

• Installation instructions are available over here

• To configure nagios with your config directories refer image below