---
title: Telegraf Documentation
description: Telegraf plugin for collecting metrics from NATS Consumer
url: https://docs.influxdata.com/telegraf/v1/input-plugins/nats_consumer/
estimated_tokens: 2688
product: Telegraf
version: v1
---

-   Telegraf v0.10.3+

# NATS Consumer Input Plugin

This service plugin consumes messages from [NATS](https://www.nats.io/about/) instances in one of the supported [data formats](/telegraf/v1/data_formats/input). A [Queue Group](https://www.nats.io/documentation/concepts/nats-queueing/) is used when subscribing to subjects so multiple instances of telegraf can consume messages in parallel. The plugin supports authenticating via [username/password](https://docs.nats.io/using-nats/developer/connecting/userpass), a [credentials file](https://docs.nats.io/using-nats/developer/connecting/creds) (NATS 2.0), or an [nkey seed file](https://docs.nats.io/using-nats/developer/connecting/nkey) (NATS 2.0).

**Introduced in:** Telegraf v0.10.3 **Tags:** messaging **OS support:** all

## Service Input

This plugin is a service input. Normal plugins gather metrics determined by the interval setting. Service plugins start a service to listen and wait for metrics or events to occur. Service plugins have two key differences from normal plugins:

1. The global or plugin specific `interval` setting may not apply
2. The CLI options of `--test`, `--test-wait`, and `--once` may not produce output for this plugin

## Tracking metric support

This plugin supports [tracking metrics](../../../docs/METRICS.md#tracking-metrics), which allows the plugin to be notified when metrics have been delivered to all outputs, enabling proper acknowledgment back to the source.

## Global configuration options

Plugins support additional global and plugin configuration settings for tasks such as modifying metrics, tags, and fields, creating aliases, and configuring plugin ordering. See [CONFIGURATION.md](/telegraf/v1/configuration/#plugins) for more details.

## Configuration

```toml
# Read metrics from NATS subject(s)
[[inputs.nats_consumer]]
  ## urls of NATS servers
  servers = ["nats://localhost:4222"]

  ## subject(s) to consume
  ## If you use jetstream you need to set the subjects
  ## in jetstream_subjects
  subjects = ["telegraf"]

  ## jetstream subjects
  ## jetstream is a streaming technology inside of nats.
  ## With jetstream the nats-server persists messages and
  ## a consumer can consume historical messages. This is
  ## useful when telegraf needs to restart it don't miss a
  ## message. You need to configure the nats-server.
  ## https://docs.nats.io/nats-concepts/jetstream.
  jetstream_subjects = ["js_telegraf"]

  ## explicitly specify the jetstream stream name
  ## useful for sourced streams where there is no subject defined and
  ## thus jetstream_subjects won't work
  jetstream_stream = ""

  ## name a queue group
  queue_group = "telegraf_consumers"

  ## Optional authentication with username and password credentials
  # username = ""
  # password = ""

  ## Optional authentication with NATS credentials file (NATS 2.0)
  # credentials = "/etc/telegraf/nats.creds"

  ## Optional authentication with nkey seed file (NATS 2.0)
  # nkey_seed = "/etc/telegraf/seed.txt"

  ## Use Transport Layer Security
  # secure = false

  ## Optional TLS Config
  # tls_ca = "/etc/telegraf/ca.pem"
  # tls_cert = "/etc/telegraf/cert.pem"
  # tls_key = "/etc/telegraf/key.pem"
  ## Use TLS but skip chain & host verification
  # insecure_skip_verify = false

  ## Sets the limits for pending msgs and bytes for each subscription
  ## These shouldn't need to be adjusted except in very high throughput scenarios
  # pending_message_limit = 65536
  # pending_bytes_limit = 67108864

  ## Max undelivered messages
  ## This plugin uses tracking metrics, which ensure messages are read to
  ## outputs before acknowledging them to the original broker to ensure data
  ## is not lost. This option sets the maximum messages to read from the
  ## broker that have not been written by an output.
  ##
  ## This value needs to be picked with awareness of the agent's
  ## metric_batch_size value as well. Setting max undelivered messages too high
  ## can result in a constant stream of data batches to the output. While
  ## setting it too low may never flush the broker's messages.
  # max_undelivered_messages = 1000

  ## Data format to consume.
  ## Each data format has its own unique set of configuration options, read
  ## more about them here:
  ## https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_INPUT.md
  data_format = "influx"
```

## Metrics

Which data you will get depends on the subjects you consume from nats

## Example Output

Depends on the nats subject input nats\_consumer,host=foo,subject=recvsubj value=1.9 1655972309339341000

#### Related

-   [Configure plugins](/telegraf/v1/configure_plugins/)
-   [NATS Consumer Plugin Source](https://github.com/influxdata/telegraf/tree/v1.38.4/plugins/inputs/nats_consumer/README.md)