# Kafka Consumer Legacy Input Plugin

**Deprecated in version 1.4. Please use [Kafka Consumer input plugin][]**

The [Kafka](http://kafka.apache.org/) consumer plugin polls a specified Kafka
topic and adds messages to InfluxDB. The plugin assumes messages follow the line
protocol. [Consumer Group][1] is used to talk to the Kafka cluster so multiple
instances of telegraf can read from the same topic in parallel.

[1]: http://godoc.org/github.com/wvanbergen/kafka/consumergroup

## Service Input <!-- @/docs/includes/service_input.md -->

This plugin is a service input. Normal plugins gather metrics determined by the
interval setting. Service plugins start a service to listens and waits 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

## Global configuration options <!-- @/docs/includes/plugin_config.md -->

In addition to the plugin-specific configuration settings, plugins support
additional global and plugin configuration settings. These settings are used to
modify metrics, tags, and field or create aliases and configure ordering, etc.
See the [CONFIGURATION.md][CONFIGURATION.md] for more details.

[CONFIGURATION.md]: ../../../docs/CONFIGURATION.md#plugins

## Configuration

```toml @sample.conf
# Read metrics from Kafka topic(s)
[[inputs.kafka_consumer_legacy]]
  ## topic(s) to consume
  topics = ["telegraf"]

  ## an array of Zookeeper connection strings
  zookeeper_peers = ["localhost:2181"]

  ## Zookeeper Chroot
  zookeeper_chroot = ""

  ## the name of the consumer group
  consumer_group = "telegraf_metrics_consumers"

  ## Offset (must be either "oldest" or "newest")
  offset = "oldest"

  ## 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"

  ## Maximum length of a message to consume, in bytes (default 0/unlimited);
  ## larger messages are dropped
  max_message_len = 65536
```

## Testing

Running integration tests requires running Zookeeper & Kafka. See Makefile
for kafka container command.

[Kafka Consumer input plugin]: ../kafka_consumer/README.md

## Metrics

## Example Output