Overview

The creates nagios server and clients that will interact with a puppetmaster be added automatically to the nagios server. You must have a puppetmaster installed with stored configs setup. It uses the puppet nagios export commands. This works on Centos 64 bit. With need changes for other platforms.

To define a server: class { 'nagios': } class { 'nagios::server': require => Class['nagios'] }

On a client:

1. Use a nrpe module like pdxcat-nrpe, http://forge.puppetlabs.com/pdxcat/nrpe, to install nrpe on all clients including the nagios server

   class { 'nrpe': allowed_hosts => ['127.0.0.1', 'monitor.pibenchmark.com'], require => Class['ntp'] }

2. Change the nrpe.cfg to have the required commands installed (probably a cleaner way to do this) a. edit the file nrpe.cfg and change allowed_hosts=127.0.0.1 to #allowed_hosts=127.0.0.1 allowed_hosts=127.0.0.1,99.99.99.99
   where 99.99.99.99is the nagios ip address

   b. replace the nrpe.cfg with this new file

   exec { 'save old nrpe.cfg': command => "cp -f nrpe.cfg nrpe.cfg.old", cwd => "/etc/nagios", require => Class['nrpe'] }

   npre config file

   file {'new nrpe.cfg': ensure => present, path => '/etc/nagios/nrpe.cfg.new', source => 'puppet:///modules/nagios/nrpe.cfg', require => Exec['save old nrpe.cfg'] }

   exec { 'move nrpe.cfg': command => "mv -f nrpe.cfg.new nrpe.cfg", cwd => "/etc/nagios", require => File['new nrpe.cfg'] }
   c. restart the nrpe service exec { 'restart the nrpe service': command => "service nrpe restart", cwd => "/tmp", require => Exec['move nrpe.cfg'] }

3. Export the client host to puppet so it will be added automatically to the nagios server. class { 'nagios::export' : require => Exec['restart the nrpe service'] }

Once this is working add additional checks for services etc.

Based on

http://www.allgoodbits.org/articles/view/31
http://www.allgoodbits.org/articles/view/32

DEBUGGING

To debug nagios config file errors run
nagios -v /etc/nagios/nagios.cfg

To test that the nrpe is running commands run on the nagios server
/usr/lib64/nagios/plugins/check_nrpe -H client.example.com -c check_load
where client.example.com is the client hostname