---
title: Use Kapacitor with InfluxDB OSS
description: Kapacitor is a data processing framework that makes it easy to create alerts, run ETL (Extract, Transform and Load) jobs and detect anomalies. Use Kapacitor with InfluxDB OSS 2.x.
url: https://docs.influxdata.com/influxdb/v2/tools/kapacitor/
estimated_tokens: 3063
product: InfluxDB OSS v2
version: v2
---

# Use Kapacitor with InfluxDB OSS

This page documents an earlier version of InfluxDB OSS. [InfluxDB 3 Core](/influxdb3/core/) is the latest stable version.

#### API token hashing is enabled by default in InfluxDB OSS 2.9.0

Stronger token security: tokens are stored as hashes on disk, so a copy of the database file doesn’t expose usable tokens. Existing tokens are hashed on first startup and the original strings can’t be recovered afterward — **capture any plaintext tokens you still need before you upgrade**.

For more information, see [Token hashing](/influxdb/v2/admin/tokens/#token-hashing).

[Kapacitor](/kapacitor/v1/) is a data processing framework that makes it easy to create alerts, run ETL jobs and detect anomalies. Kapacitor interacts with **InfluxDB Cloud** and **InfluxDB OSS 2.9** using the [InfluxDB 1.x compatibility API](/influxdb/v2/reference/api/influxdb-1x/), so you can continue using Kapacitor without having to migrate libraries of TICKscripts to InfluxDB tasks.

#### Support for stream tasks

InfluxDB Cloud and InfluxDB OSS 2.9 do not have subscription APIs and **do not support Kapacitor stream tasks**, but you can continue to use stream tasks by writing data directly to Kapacitor. For more information, see [below](#use-kapacitor-stream-tasks).

#### On this page

-   [Configure Kapacitor to connect to InfluxDB](#configure-kapacitor-to-connect-to-influxdb)
-   [Use Kapacitor batch tasks](#use-kapacitor-batch-tasks)
-   [Use Kapacitor stream tasks](#use-kapacitor-stream-tasks)
-   [Write back to InfluxDB](#write-back-to-influxdb)

## Configure Kapacitor to connect to InfluxDB

To connect Kapacitor to InfluxDB Cloud or InfluxDB OSS 2.9, update the `[[influxdb]]` section(s) of your [Kapacitor configuration file](/kapacitor/v1/administration/configuration/#kapacitor-configuration-file):

-   [Specify your InfluxDB URL](#specify-your-influxdb-url)
-   [Provide InfluxDB authentication credentials](#provide-influxdb-authentication-credentials)
-   [Disable InfluxDB subscriptions](#disable-influxdb-subscriptions)

### Specify your InfluxDB URL

Provide your InfluxDB URL in the `[[influxdb]].urls` configuration option. For more information, see [InfluxDB Cloud regions](/influxdb/cloud/reference/regions/) or [InfluxDB OSS URLs](/influxdb/v2/reference/urls/).

```toml
[[influxdb]]
  # ...
  urls = ["http://localhost:8086"]
```

### Provide InfluxDB authentication credentials

InfluxDB Cloud and InfluxDB OSS 2.9 require authentication. Provide the following credentials in your `[[influxdb]].username` and `[[influxdb]].password` configuration options:

-   **username:** InfluxDB username
-   **password:** InfluxDB [API token](/influxdb/v2/admin/tokens/)

```toml
[[influxdb]]
  # ...
  username = "influxdb-username"
  password = "influxdb-token"
```

Kapacitor is subject to InfluxDB token permission restrictions. To query or write to an InfluxDB bucket, the InfluxDB token must have read and/or write permissions for the target bucket. For information about token permissions, see [Create a token](/influxdb/v2/admin/tokens/create-token/).

### Disable InfluxDB subscriptions

InfluxDB Cloud and InfluxDB OSS 2.9 do not have subscriptions APIs. Set the `[[influxdb]].disable-subscriptions`to `true` to disable InfluxDB subscriptions.

```toml
[[influxdb]]
  # ...
  disable-subscriptions = true
```

## Use Kapacitor batch tasks

Kapacitor batch tasks use the `query` endpoint of the 1.x compatibility API and require no change to use with InfluxDB Cloud and InfluxDB OSS. For information about writing back to InfluxDB in Kapacitor tasks, see [Write back to InfluxDB](#write-back-to-influxdb) below.

## Use Kapacitor stream tasks

InfluxDB Cloud and OSS 2.9 do not have subscription APIs and do not support Kapacitor stream tasks directly. To use Kapacitor stream tasks, write data directly to Kapacitor using the [Kapacitor `write` API](/kapacitor/v1/working/api/#writing-data). We recommend using the [Telegraf InfluxDB output plugin](/telegraf/v1/plugins/#output-influxdb) to write data to both InfluxDB Cloud or OSS and Kapacitor.

##### Write data using the Telegraf InfluxDB output plugin

To write data to both InfluxDB and Kapacitor using the InfluxDB output plugin, complete the following steps:

1. [Install Telegraf](/telegraf/v1/install/).
2. [Create a DBRP mapping](/influxdb/v2/query-data/influxql/dbrp/#create-dbrp-mappings).
3. In the [Telegraf InfluxDB output plugin](/telegraf/v1/plugins/#output-influxdb) configuration file, specify the following options, replacing `database`, `retention_policy`, `username` and `password` to match your DBRP mapping, and set `skip_database_creation` to `true`:

```toml
# Write to Kapacitor
[[outputs.influxdb]]
  urls = ["http://localhost:9092"]
  database = "example-db"
  retention_policy = "example-rp"

# Write to InfluxDB Cloud or OSS
[[outputs.influxdb]]
  urls = ["http://localhost:8086"]
  database = "example-db"
  retention_policy = "example-rp"
  username = "influxdb-username"
  password = "influxdb-token"
  skip_database_creation = true
```

## Write back to InfluxDB

If using the Kapacitor `InfluxDBOut` node to write data to InfluxDB 2.9, InfluxDB maps the specified database and retention policy to a corresponding bucket. You can also manually map database/retention policy combinations (DBRPs) to buckets. For more information, see [DBRP mapping](/influxdb/v2/reference/api/influxdb-1x/dbrp/).

The following example TICKscript writes to the `my-db/my-rp` bucket in InfluxDB Cloud or InfluxDB OSS 2.9.

```js
batch
  |query('SELECT errors / total AS error_percent from requests')
  // Write the transformed data to InfluxDB
  |influxDBOut()
    .database('my-db')
    .retentionPolicy('my-rp')
    .measurement('errors')
    .tag('kapacitor', 'true')
    .tag('version', '0.2')
```

#### Related

-   [Kapacitor documentation](/kapacitor/v1/)