syslog_ng

Table of Contents

• Overview
• Module Description
  • Configuration syntax
• Setup
  • Puppet Forge
  • Installing from source
  • What syslog_ng affects
  • Getting started with syslog_ng
• Usage
  • Facts
  • Classes and defined types
• Implementation details
• Limitations
• Development
  • Tests
  • Other information

Overview

This module lets you generate syslog-ng configuration using puppet. It supports all kinds of statements, such as sources, destinations, templates, and so on. After defining them, you can combine them into a log path. This module also takes care of installing syslog-ng, or reloading it after a configuration file change.

You can check the supported platforms in the Limitations section.

Module Description

This module integrates well with syslog-ng. It supports its configuration model so you can create new sources and destinations as Puppet resources. Under the hood they are just defined resource types.

The supported statements:

• options
• template
• rewrite
• parser
• filter (partial support)
• source
• destination
• log
• +1: config, which lets you insert existing configuration snippets.

Each type is under the syslog_ng:: namespace, so you can use them like this:

syslog_ng::source { 's_gsoc':
    params => {
        'type' => 'tcp',
        'options' => [
            {'ip' => "'127.0.0.1'"},
            {'port' => 1999}
        }]
    }
}

There is a shorter form:

syslog_ng::source { 's_gsoc':
    params => {
        'tcp' => [
            {'ip' => "'127.0.0.1'"},
            {'port' => 1999}
        }]
    }
}

Configuration syntax

Every statement has the same layout. They can accept a params parameter, which can be a hash or an array of hashes. Each hash should have a type and options key or you can use a shorter form.

The value of the type represents the type of the statement, in case of a source this can be file, tcp and so on.

The value of the options is an array of strings and hashes. You have to pay attention to quotation when using strings. If you want the inner quotation to be a single quote ( in the syslog-ng.conf), then the outer one must be a double, like "'this string'", which will be transformed into 'this string'.

Similarly, you can write '"this string"'' to get "this string" in the configuration.

By using this convention, the module will generate correct configuration files. If the option array is empty, you can use an empty string '' instead.

As I mentioned, there are strings and hashes in an option. Hashes must contain only one key. This key will identify the name of the parameter and its value must be an array of strings. If that would contain only one item, the value can be simply just a string.

You can find a lot of examples under the tests and spec directories. The default_config.pp under the tests directory contains the default configuration from the syslog-ng source, translated into Puppet types.

Setup

Puppet Forge

This module is published on Puppet Forge. It used to be under the ihrwein namespace, but the original author kindly accepted to hand it over.

Installing from source

You can install it following these steps:

0. Make sure you have the required dependencies

• ruby
• bundler

1. Clone the source code into a directory:

$ git clone https://github.com/ccin2p3/puppet-syslog_ng.git

2. Make sure you are on master branch:

$ git checkout master

3. Get dependencies

$ bundle install

4. Build a package:

$ bundle exec puppet module build

This will create a tar.gz file under the pkg directory. Now you should be able to install the module:

$ bundle exec puppet module install pkg/ccin2p3-syslog_ng-VERSION.tar.gz

What syslog_ng affects

• It setup a repository with recent syslog-ng releases (only on RedHat and Debian based operating systems and if $syslog_ng::manage_repo is set to true)
• It installs the syslog-ng or syslog-ng-core package
  • that creates the necessary directories on your system, including /etc/syslog-ng.
  • If another syslog daemon is installed, it will be removed by your package manager.
• purges the content of /etc/syslog-ng/syslog-ng.conf

Getting started with syslog_ng

If you are not familiar with syslog-ng, I suggest you to take a look at the Syslog-ng Admin Guide which contains all the necessary information to use this software.

You can also get help on the syslog-ng mailing list.

Usage

Just use the classes and defined types as you would use them, without Puppet.

Before the generated configuration would be applied, it is written to a temporary file. Next, the module checks the configuration syntax of this file, and if it is OK, it overwrites the real configuration file. So you do not have to worry about configuration errors.

Facts

The fact syslog_ng_version contains the installed version string e.g. 3.7.1

Classes and defined types

For information on the classes and types, see the REFERENCE.md.

Implementation details

There is a concat::fragment resource in every class or defined type which represents a statement. Because statements need to be defined before they are referenced in the configuration, I use an automatic ordering system. Each type has its own order value, which determines its position in the configuration file. The smaller an order value is, the more likely it will be at the beginning of the file. The interval of these values starts with 0 and are 'strings'. Here is a table, which contains the default order values:

Name	Order
syslog_ng::config	'5'
syslog_ng::destination	'70'
syslog_ng::filter	'50'
syslog_ng::log	'80'
syslog_ng::options	'10'
syslog_ng::parser	'40'
syslog_ng::rewrite	'30'
syslog_ng::source	'60'
syslog_ng::template	'20'

The config generation is done by the generate_statement() function in most cases. It is just a wrapper around my statement.rb Ruby module, which does the hard work. The require part may seem quite ugly, but it works well.

Limitations

The module works well with the following Puppet versions:

• 2.7.9
• 2.7.13
• 2.7.17
• 3.1.0
• 3.2.3
• 3.3.1
• 3.3.2
• 3.4.0
• 3.4.3

Tested Ruby versions:

• 1.8.7
• 1.9.2

NOTE: The module was tested with Travis with these versions. It may work well on other Puppet or Ruby versions. If that's so, please hit me up.

The following platforms are currently tested (in Docker containers):

	1.8.7	1.9.1	1.9.3	2.0.0
CentOS 6	x
CentOS 7				x
Ubuntu 12.04	x
Ubuntu 14.04			x

If you use it on an other platform, please let me know about it!

Development

Tests

This module use the Voxpupuli tooling, so the Voxpupuli documentation apply about [how to run the test suite=(https://voxpupuli.org/docs/how_to_run_tests/).

Other information

I am open to any pull requests, either for bug fixes or feature developments. I cannot stress the significance of tests sufficiently, so please, write some spec tests and update the documentation as well according to your modification.

Note for commiters:

The master branch is a sacred place, do not commit to it directly, we should touch it only using pull requests.