Fluentd

Monitoring by REST API

This article describes how to get the internal Fluentd metrics via the REST API.

Monitoring Agent

Fluentd has a monitoring agent to retrieve internal metrics in JSON format via HTTP.

Add these lines to your configuration file:

<source>
  @type monitor_agent
  bind 0.0.0.0
  port 24220
</source>

Restart the agent and get the metrics via HTTP:

$ curl http://host:24220/api/plugins.json
{
  "plugins":[
    {
      "plugin_id":"object:3fec669d6ac4",
      "plugin_category":"input",
      "type":"forward",
      "output_plugin":false,
      "retry_count":null,
      "emit_records":0,
      "emit_size":0
    },
    {
      "plugin_id":"object:3fec669dfa48",
      "plugin_category":"input",
      "type":"monitor_agent",
      "output_plugin":false,
      "retry_count":null,
      "emit_records":0,
      "emit_size":0
    },
    {
      "plugin_id":"object:3fec66aead48",
      "plugin_category":"output",
      "type":"forward",
      "output_plugin":true,
      "buffer_queue_length":0,
      "buffer_total_queued_size":0,
      "retry_count":0,
      "emit_records":0,
      "emit_size":0
    }
  ]
}

Since v1.19.3, the config and retry fields are not included by default. Set include_config or include_retry to true if you need them.

See in_monitor_agent article for more detail.

Monitoring the Event Flow

Use flowcounter or flowcounter_simple plugin.

Datadog (dd-agent) Integration

Datadog is a cloud monitoring service, and its monitoring agent dd-agent has native integration with Fluentd.

For more details:

• Datadog-Fluentd Integration