Ticket #211: Set Up Nagios Monitoring Using Puppet Module - SupaHotBall/OE2-Group-D GitHub Wiki

Task

Create Puppet Module:

• Use a Puppet module to install Nagios on the designated server.
• Ensure all dependencies are resolved during installation.
• Apply the Puppet manifest to automate Nagios setup and configuration.
• Verify that Nagios is running and monitoring systems as expected

Configure Nagios:

• Set up Nagios to monitor the database server.
• Use Puppet to manage Nagios configuration files .

Documentation:

• Document the Puppet module structure, parameters, and usage.
• Include troubleshooting steps and solutions if any issues arise.

Validation:

• Test Nagios monitoring functionality.
• Ensure alerts and notifications are working correctly.

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Steps Taken

Create the directory for the nagios module in the puppet modules directory

sudo mkdir /etc/puppetlabs/code/modules/nagios

Inside the nagios module directory; create the manifests, files and templates directories

sudo mkdir /etc/puppetlabs/code/modules/nagios/manifests
sudo mkdir /etc/puppetlabs/code/modules/nagios/files
sudo mkdir /etc/puppetlabs/code/modules/nagios/templates

Create the .pp files within the manifests directory

sudo nano /etc/puppetlabs/code/modules/nagios/manifests/config.pp
sudo nano /etc/puppetlabs/code/modules/nagios/manifests/init.pp
sudo nano /etc/puppetlabs/code/modules/nagios/manifests/install.pp
sudo nano /etc/puppetlabs/code/modules/nagios/manifests/service.pp

Configure the install class in the install.pp file

class nagios::install {
    package { "nagios4":
        ensure  => present,
        require => User["nagios"],
    }

   user { "nagios":
       ensure  => present,
       comment => "Nagios user",
       gid     => "nagios",
       shell   => "/bin/false",
       require => Group["nagios"],
     }

   group { "nagios":
       ensure => present,
    }
}

Ensure that the nagios class is created in the init.pp file

class nagios {
  include nagios::install
}

Configure the service.pp file next

Test that the configuration has applied to the server

sudo puppet agent --test
sudo systemctl status nagios4.service

Ensure that the service class is included in the init.pp file.

Create the htpasswd.users file and add nagiosadmin as the user

sudo htpasswd -c /etc/puppetlabs/code/environments/production/modules/nagios/files/htpasswd.users nagiosadmin

Configure the config.pp file

class nagios::config {
    file { "/etc/nagios4/nagios.cfg":
        ensure  => present,
        source  => "puppet:///modules/nagios/nagios.cfg",
        mode    => "0444",
        owner   => "root",
        group   => "root",
        require => Class["nagios::install"],
        notify  => Class["nagios::service"],
    }

    file { "/etc/nagios4/htpasswd.users":
        ensure  => present,
        source  => "puppet:///modules/nagios/htpasswd.users",
        mode    => "0644",
        owner   => "root",
        group   => "root",
        require => Class["nagios::install"],
        notify  => Class["nagios::service"],
    }

    file { "/etc/nagios4/conf.d":
        ensure  => directory,
        mode    => "0775",
        owner   => "root",
        group   => "puppet",
        require => Class["nagios::install"],
    }

    nagios_host { "db-x.oe2.org.nz":
        target               => "/etc/nagios4/conf.d/ppt_hosts.cfg",
        alias                => "db",
        check_period         => "24x7",
        max_check_attempts   => 3,
        check_command        => "check-host-alive",
        notification_interval => 30,
        notification_period  => "24x7",
        notification_options => "d,u,r",
        mode                 => "0444",
    }
}

Apply the module

sudo puppet agent --test

Install the puppet nagios plugin on the puppet master

puppet module install puppetlabs-nagios core

Check Apache configuration. Open the Nagios Apache config file at /etc/apache2/conf-enabled/nagios4-cgi.conf Edit the configuration to allow all ips

Restart apache2.service and nagios4.service to ensure that the changes are applied

Check that the web interface for Nagios is accessible

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Challenges

Error: Systemd start for nagios failed!
journalctl log for nagios:
-- No entries --

Error: /Stage[main]/Nagios::Service/Service[nagios]/ensure: change from 'stopped                                                                                                                                                                                               ' to 'running' failed: Systemd start for nagios failed!
journalctl log for nagios:
-- No entries --

The above error was encountered while trying to apply the service.pp configuration to the server with puppet agent test. The reason for this error was because the service name in the file was named incorrectly as "nagios" instead of "nagios4" which is the correct name of the service. Once this was changed, the configuration applied successfully.

To fix the issue of cgi files being downloaded instead of executed, enable the cgi module.

a2endmod cgi

Restart apache2 after

systemctl restart apache2

Language validation error in the init.pp file

This error was caused by a typo within the init.pp file. It was resolved and the configuration applied successfully after correcting the language

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External Resources

N/A

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Ticket Reference

https://rt.dataraster.com/Ticket/Display.html?id=211

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