# puppet-icinga2 Installation

## Requirements

For Ubuntu systems, this module requires the [Puppet Labs apt module](https://github.com/puppetlabs/puppetlabs-apt).

On EL-based systems (CentOS, Red Hat Enterprise Linux, Fedora, etc.), the [EPEL package repository](https://fedoraproject.org/wiki/EPEL) is required.

### Server requirements

Icinga 2 requires either a [MySQL](http://www.mysql.com/) or a [Postgres](http://www.postgresql.org/) database.

Currently, this module does not set up any databases. You'll have to create one before installing Icinga 2 via the module.

If you would like to set up your own database, either of the Puppet Labs [MySQL](https://github.com/puppetlabs/puppetlabs-mysql) or [Postgres](https://github.com/puppetlabs/puppetlabs-postgresql) modules can be used. 

Database connection parameters can be specified by the `db_host`, `db_port`, `db_name`, `db_user` and `db_password` parameters.

The example below shows the [Puppet Labs Postgres module](https://github.com/puppetlabs/puppetlabs-postgresql) being used to install Postgres and create a database and database user for Icinga 2:

<pre>
  class { 'postgresql::server': }

  postgresql::server::db { 'icinga2_data':
    user     => 'icinga2',
    password => postgresql_password('icinga2', 'password'),
  }
</pre>

For production use, you'll probably want to get the database password via a [Hiera lookup](http://docs.puppetlabs.com/hiera/1/puppet.html) so the password isn't sitting in your site manifests in plain text.

To configure Icinga with the password you set up for the Postgres Icinga user, use the `server_db_password` parameter (shown here with a Hiera lookup):

<pre>
  class { 'icinga2::server':
    server_db_password => hiera('icinga_db_password_key_here')
  }
</pre>

##Usage

###Server usage

To install Icinga 2 with a Postgres database, first set up the database.

Once the database is set up, use the `icinga2::server` class with the database connection parameters to specify 

<pre>
#Install Icinga 2:
class { 'icinga2::server': 
  server_db_type => 'pgsql',
  db_host => 'localhost'
  db_port => '5432'
  db_name => 'icinga2_data'
  db_user => 'icinga2'
  db_password => 'password',
}
</pre>

When the `server_db_type` parameter is set, the right IDO database connection packages are automatically installed and the schema is loaded.

**Note:** For production use, you'll probably want to get the database password via a [Hiera lookup](http://docs.puppetlabs.com/hiera/1/puppet.html) so the password isn't sitting in your site manifests in plain text:

<pre>
#Install Icinga 2:
class { 'icinga2::server': 
  server_db_type => 'pgsql',
  db_host => 'localhost'
  db_port => '5432'
  db_name => 'icinga2_data'
  db_user => 'icinga2'
  db_password => hiera('icinga_db_password_key_here'),
}
</pre>

**Note:** If you will be installing NRPE or the Nagios plugins packages with the `icinga2::nrpe` class on a node that also has the `icinga2::server` class applied, be sure to set the `$server_install_nagios_plugins` parameter in your call to `icinga2::server` to `false`:

<pre>
#Install Icinga 2:
class { 'icinga2::server': 
  ...
  server_install_nagios_plugins => false,
  ...
 }
</pre>

This will stop the `icinga2::server` class from trying to install the plugins pacakges, since the `icinga2::nrpe` class will already be installing them and will prevent a resulting duplicate resource error.

###Client usage

To install NRPE and allow the local machine and Icinga 2 servers (or Icinga 1 or plain old Nagios servers) with various IP addresess to connect:

<pre>
class { 'icinga2::nrpe':
  nrpe_allowed_hosts => ['10.0.1.79', '10.0.1.80', '10.0.1.85', '127.0.0.1'],
}
</pre>

**Note:** If you would like to install NRPE on a node that also has the `icinga2::server` class applied, be sure to set the `$server_install_nagios_plugins` parameter in your call to `icinga2::server` to `false`:

<pre>
#Install Icinga 2:
class { 'icinga2::server': 
  server_db_type => 'pgsql',
  server_install_nagios_plugins => false,
 }
</pre>

This will stop the `icinga2::server` class from trying to install the plugins pacakges, since the `icinga2::nrpe` class will already be installing them and will prevent a resulting duplicate resource error.

###Object type usage

This module includes several defined types that can be used to automatically generate Icinga 2 format object definitions. They function in a similar way to [the built-in Nagios types that are included in Puppet](http://docs.puppetlabs.com/guides/exported_resources.html#exported-resources-with-nagios).

####Exported resources

Like the built-in Nagios types, they can be exported to PuppetDB as virtual resources and collected on your Icinga 2 server.

Nodes that are being monitored can have the `@@` virtual resources applied to them:

<pre>
@@icinga2::object::host { $::fqdn:
  display_name => $::fqdn,
  ipv4_address => $::ipaddress_eth0,
  groups => ['linux_servers', 'mysql_servers'],
  vars => {
    os              => 'linux',
    virtual_machine => 'true',
    distro          => $::operatingsystem,
  },
  target_dir => '/etc/icinga2/objects/hosts',
  target_file_name => "${fqdn}.conf"
}
</pre>

Then, on your Icinga 2 server, you can collect the exported virtual resources (notice the camel casing in the class name):

<pre>
#Collect all @@icinga2::object::host resources from PuppetDB that were exported by other machines:
Icinga2::Object::Host <<| |>> { }
</pre>

Unlike the built-in Nagios types, the file owner, group and mode of the automatically generated files can be controlled via the `target_file_owner`, `target_file_group` and `target_file_mode` parameters:

<pre>
@@icinga2::object::host { $::fqdn:
  display_name => $::fqdn,
  ipv4_address => $::ipaddress_eth0,
  groups => ['linux_servers', 'mysql_servers'],
  vars => {
    os              => 'linux',
    virtual_machine => 'true',
    distro          => $::operatingsystem,
  },
  target_dir        => '/etc/icinga2/objects/hosts',
  target_file_name  => "${fqdn}.conf"
  target_file_owner => 'root',
  target_file_group => 'root',
  target_file_mode  => '644'
}
</pre>

####`undef` and default object values

Most of the object parameters *in the Puppet module* are set to **undef**. 

This means that they will not be added to the rendered object definition files.

**However**, this doesn't mean that the values are undefined in Icinga 2. Icinga 2 itself has built-in default values for many object parameters and falls back to them if one isn't present in an object definition. See the docs for individual object types in [Configuring Icinga 2](http://docs.icinga.org/icinga2/latest/doc/module/icinga2/toc#!/icinga2/latest/doc/module/icinga2/chapter/configuring-icinga2) for more info about which object parameters have what default values. 

####`icinga2::object::host`

**Note:** The `ipv6_address` parameter is set to **undef** by default. This is because `facter` can return either IPv4 or IPv6 addresses for the `ipaddress_ethX` facts. The default value for the `ipv6_address` parameter is set to **undef** and not `ipaddress_eth0` so that an IPv4 address isn't unintentionally set as the value for `address6` in the rendered host object definition.

If you would like to use an IPv6 address, make sure to set the `ipv6_address` parameter to the `ipaddress_ethX` fact that will give you the right IPv6 address for the machine:

<pre>
@@icinga2::object::host { $::fqdn:
  display_name => $::fqdn,
  ipv6_address => $::ipaddress_eth1,
....
}
</pre>

####`icinga2::object::apply_service_to_host`

The `apply_service_to_host` defined type can create `apply` objects to apply services to hosts:

<pre>
#Create an apply that checks the number of zombie processes:
icinga2::object::apply_service_to_host { 'check_zombie_procs':
  display_name => 'Zombie procs',
  check_command => 'nrpe',
  vars => {
    nrpe_command => 'check_zombie_procs',
  },
  assign_where => '"linux_servers" in host.groups',
  ignore_where => 'host.name == "localhost"',
  target_dir => '/etc/icinga2/objects/applys'
}
</pre>

This defined type has the same available parameters that the `icinga2::object::service` defined type does.

The `assign_where` and `ignore_where` parameter values are meant to be provided as strings. Since Icinga 2 requires that string literals be double-quoted, the whole string in your Puppet site manifests will have to be single-quoted (leaving the double quotes intact inside):

<pre>
assign_where => '"linux_servers" in host.groups',
</pre>

If you would like to use Puppet or Facter variables in an `assign_where` or `ignore_where` parameter's value, you'll first need to double-quote the whole value for [Puppet's variable interpolation](http://docs.puppetlabs.com/puppet/latest/reference/lang_datatypes.html#double-quoted-strings) to work. Then, you'll need to escape the double quotes that surround the Icinga 2 string literals inside:

<pre>
assign_where => "\"linux_servers\" in host.${facter_variable}"",
</pre>