Ansible role to install and configure Server Density Agent

Server Density is a monitoring solution which requires a simple Python based agent and is highly configurable. This Ansible role installs and confgures that agent and supports several options like plugin installation and inventory synchronisation with your Server density dashboard.

Currently this plugin is developed and tested for Ubuntu only and will be enhanced to other Nix's later on.

Dependency

The Ansible-ServerDensity-Plugin is required and installation and instructions can be found in that project.

Configuration

In defaults/main.yml you'll find a set of variables that you could re-define in your own inventory. Please, do not overwrite the variables in defaults/main.yml, instead you should define them in your inventory files, e.g. group_vars/all

sd_url

Default: ''

Defines the Server Density URL of your account, e.g. 'https://myaccount.serverdensity.io'

sd_api_token

Default: ''

Defines your API token provided by Server Density. You get this token by going to preferences in your SD account to the "Security" tab where you can either grab one of the existing API tokens or createing a new one.

sd_api_cache_file

Default: no

Each time you're using the SD plugin it reads the current settings for devices, services and alerts from your SD account by using the Server Density API. As this usually takes a couple of seconds it is possible to shortcut that process by storing all those settings in a cache file of your own choice so that next time those values get loaded from that cache file instead through the API.

The plugin makes sure that the cache gets reset if necessary, e.g. if the settings of your inventory have changed.

sd_agent_key

Default: ''

Do not redefine this variable, it is just there to avoid error messages in case a variable was missing. The agent key for each of your hosts gets assigned by Server Density and ill be imported by the plugin and will be used for updating your device settings.

sd_logging_level

Default: 'info'

Defines the level of log information that the SD agent will produce during run time. Possible values are debug, info, error, warn, warning, critical, fatal

sd_plugins

Default: []

Defines a list of Server Density plugins that will be installed and updated by this role automatically.

Example:

  sd_plugins:
    updatestatus: UpdateStatus.py
    redis: Redis.py

This variable is expected to be defined as a set so that hash_behaviour=merge can be used so that you can define this variable in several of your groups and that this role is going to install the superset of all the group a specific host belings to.

The key of each entry should be unique across your inventory and the value is a file name. Those files have to be present in a subdirectory called files/sd-plugins of your inventory directory.

sd_groups

Default:

  apache: none
  mysql: none
  proxy: none

Certain sections in the agent configuration are only relevant for certain hosts and by providing valid inventory group names for those sections (currently apache, mysql, proxy) you can make sure that for all hosts in those groups the relevant parts in the agent configuration get written to that host.

Detailed configuration for inventory synchronisation

By defining further variables in your inventory, you get full control over how your inventory gets synchronized with your Server Density dashboard including device groups, services and alerts.

All those options are documented over in the Ansible-ServerDensity-Plugin