Ansible Role Prometheus Exporter

Description

❕ Before using this role, please know that all my Ansible roles are fully written and accustomed to my IT infrastructure. So, even if they are as generic as possible they will not necessarily fill your needs, I advice you to carrefully analyse what they do and evaluate their capability to be installed securely on your servers.

This roles can install and configure most of the prometheus exporter.

Requirements

Require Ansible >= 2.4

Dependencies

OS Family

This role is available for Debian and CentOS

Features

At this day the role can be used to :

• install exporter using corresponding host architecture
• configure exporter
  • binary capabilities
  • custom files
  • service command line
• configure a systemd service to launch the exporter
• known exporters : node_exporter, blackbox_exporter
• local facts

Configuration

Role

All variables which can be overridden are stored in defaults/main.yml file as well as in table below. To see default values please refer to this file.

Name	Type	Description
prometheus_exporter__name	String	The exporter name (use the official name here)
prometheus_exporter__download_url	Url	If the exporter name is not known by the role, you must provide the download url (see example below)
prometheus_exporter__checksum_url	Url	If the exporter name is not known by the role, you must provide the checksum url (see example below)
prometheus_exporter__temporary_file_extension	String	If the exporter name is not known by the role, you must fill here with downloaded file's extension (see example below)
prometheus_exporter__version	String	This variable has default value on [name of the exporter]+__version variable. It can be used as a placeholder in url (see example)
prometheus_exporter__service_user	String	Specify the system user with which the exporter will be run, this value is auto generated if not filled
prometheus_exporter__service_group	String	Specify the system group with which the exporter will be run, this value is auto generated if not filled
prometheus_exporter__service_enabled	Boolean	Enable or not the systemd service
prometheus_exporter__service_cmdline	String/List of Strings	The command line arguments that will be given to executable
prometheus_exporter__create_directories	List of directories definitions	Will create the given list of directories before to run the exporter (see below)
prometheus_exporter__create_files	List of files definitions	Will create the given list of file before to run the exporter (see below)
prometheus_exporter__capabilities	List of String	List of capabilities to apply on exporter executable

Installation and configuration

By default some exporters are known, so you have not to fill the download url, checksum url and others options. But if you want to install your own exporter, you have juste to fill theses settings. Then the installation procedure must be "the same" for all exporter

Custom directories

The prometheus_exporter__create_directories variable allow custom directories creation before to start the exporter. It take a list of directories definition, each definition call the official "file" module.

Custom files

The prometheus_exporter__create_files variable allow custom files creation before to start the exporter. It need a list of files definitions. Each file definition accept common file attributes plus 'content' or 'template'. If 'template' is used, the 'template' module will be call to produce the file's content. So encure that the template file is reacheable. If 'content' is used, the 'copy' module will be call to directly produce the file's content.

Known Exporters

Node exporter

Name	Type	Description
node_exporter__web_listen_address	String	The ipaddress + port on which the exporter will listen
node_exporter__web_telemetry_path	String	The path prefix on which to serve the metrics
node_exporter__enabled_collectors_global/group/host	List of String/Dict	Define collectors to enable with optional options (see below)
node_exporter__disabled_collectors_global/group/host	List of String	Disable theses collectors (theses names must not be in the enabled list)
node_exporter__textfile_directory	String	The path where the local disk statistics collector will read metrics

Some node-exporter collectors' accepts options. In the variables node_exporter__enabled_collectors_* you can pass simple string and dict

If you use simple string, the collector will simply be enabled.

If you specify a dict, the collector will be enabled and all dict key-value will be passed as collector options (see example with filesystem below)

Blackbox exporter

Name	Type	Description
blackbox_exporter__web_listen_address	String	The ipaddress + port on which the exporter will listen
blackbox_exporter__config	String/Mixed	The raw blackbox yaml configuration file. If this variable is a dict, it will be yamlized before being written to the file

Facts

By default the local fact are installed and expose the following variables :

ansible_local.[exporter name]:
    version_full: "1.0.0"
    version_major: "1"

Example

Playbook

• Install and configure a built-in exporter type as follows:

- hosts: all
  roles:
    - role: turgon37.prometheus_exporter
      vars:
        prometheus_exporter__name: node_exporter

• Install and configure a non built-in exporter type as follows :

- hosts: all
  roles:
    - role: turgon37.prometheus_exporter
      vars:
        prometheus_exporter__name: mysqld_exporter
        prometheus_exporter__download_url: 
          "https://github.com/prometheus/mysqld_exporter/releases/download/\
          v{{ prometheus_exporter__version }}/\
          mysqld_exporter-{{ prometheus_exporter__version }}.linux\
          -{{ prometheus_exporter__go_arch_map[ansible_architecture]|d(ansible_architecture) }}.tar.gz"
        mysqld_exporter__version: 0.11.0
        prometheus_exporter__temporary_file_extension: .tar.gz
        prometheus_exporter__service_cmdline: >-
          --config.my-cnf /etc/mysql/monitoring.cnf

Node exporter

node_exporter__version: 0.17.0

# using a global exporters port map defined in your inventory to prevent overlap
node_exporter__web_listen_address: 127.0.0.1:{{ _prometheus_exporter_ports_map['node'] }}"
node_exporter__enabled_collectors_global:
  - ntp
  - filesystem:
      ignored-mount-points: "^/(sys|proc|dev)($|/)"
      ignored-fs-types: "^(sys|pr-c|auto)fs$"

Blackbox exporter

blackbox_exporter__version: 0.14.0

prometheus_exporter__capabilities:
  - cap_net_raw+ep

blackbox_exporter__config:
  modules:
    http_2xx:
      prober: http
      timeout: 5s
      http:
        method: GET
        valid_status_codes: []
        no_follow_redirects: true
        fail_if_ssl: false
        fail_if_not_ssl: false
        preferred_ip_protocol: ip4
    icmp:
      prober: icmp
      icmp:
        preferred_ip_protocol: ip4
        dont_fragment: true
        payload_size: 500