[[set-up-tsds]]
=== Set up a time series data stream (TSDS)
++++
<titleabbrev>Set up a TSDS</titleabbrev>
++++

preview::[]

To set up a <<tsds,time series data stream (TSDS)>>, follow these steps:

. Check the <<tsds-prereqs,prerequisites>>.
. <<tsds-ilm-policy>>.
. <<tsds-create-mappings-component-template>>.
. <<tsds-create-index-settings-component-template>>.
. <<create-tsds-index-template>>.
. <<create-tsds>>.
. <<secure-tsds>>.

[discrete]
[[tsds-prereqs]]
==== Prerequisites

* Before you create a TSDS, you should be familiar with <<data-streams,data
streams>> and <<tsds,TSDS concepts>>.

* To follow this tutorial, you must have the following permissions:

** <<privileges-list-cluster,Cluster privileges>>: `manage_ilm` and
`manage_index_templates`.
** <<privileges-list-indices,Index privileges>>: `create_doc` and `create_index`
for any TSDS you create or convert. To roll over a TSDS, you must have the
`manage` privilege.

[discrete]
[[tsds-ilm-policy]]
==== Create an index lifecycle policy

While optional, we recommend using {ilm-init} to automate the management of your
TSDS's backing indices. {ilm-init} requires an index lifecycle policy.

We recommend you specify a `max_age` criteria for the `rollover` action in the
policy. This ensures the <<time-bound-indices,`@timestamp` ranges>> for the
TSDS's backing indices are consistent. For example, setting a `max_age` of `1d`
for the `rollover` action ensures your backing indices consistently contain one
day's worth of data.

////
[source,console]
----
PUT /_snapshot/found-snapshots
{
 "type": "fs",
  "settings": {
    "location": "my_backup_location"
  }
}
----
// TESTSETUP
////

[source,console]
----
PUT _ilm/policy/my-weather-sensor-lifecycle-policy
{
  "policy": {
    "phases": {
      "hot": {
        "actions": {
          "rollover": {
            "max_age": "1d",
            "max_primary_shard_size": "50gb"
          }
        }
      },
      "warm": {
        "min_age": "30d",
        "actions": {
          "shrink": {
            "number_of_shards": 1
          },
          "forcemerge": {
            "max_num_segments": 1
          }
        }
      },
      "cold": {
        "min_age": "60d",
        "actions": {
          "searchable_snapshot": {
            "snapshot_repository": "found-snapshots"
          }
        }
      },
      "frozen": {
        "min_age": "90d",
        "actions": {
          "searchable_snapshot": {
            "snapshot_repository": "found-snapshots"
          }
        }
      },
      "delete": {
        "min_age": "735d",
        "actions": {
          "delete": {}
        }
      }
    }
  }
}
----

[discrete]
[[tsds-create-mappings-component-template]]
==== Create a mappings component template

A TSDS requires a matching index template. In most cases, you compose this index
template using one or more component templates. You typically use separate
component templates for mappings and index settings. This lets you reuse the
component templates in multiple index templates.

For a TSDS, the mappings component template must include mappings for:

* One or more <<time-series-dimension,dimension fields>> with a
`time_series_dimension` value of `true`. At least one of these dimensions must
be a plain `keyword` field.

Optionally, the template can also include mappings for:

* One or more <<time-series-metric,metric fields>>, marked using the
`time_series_metric` mapping parameter.

* A `date` or `date_nanos` mapping for the `@timestamp` field. If you don’t
specify a mapping, Elasticsearch maps `@timestamp` as a `date` field with
default options.

[source,console]
----
PUT _component_template/my-weather-sensor-mappings
{
  "template": {
    "mappings": {
      "properties": {
        "sensor_id": {
          "type": "keyword",
          "time_series_dimension": true
        },
        "location": {
          "type": "keyword",
          "time_series_dimension": true
        },
        "temperature": {
          "type": "half_float",
          "time_series_metric": "gauge"
        },
        "humidity": {
          "type": "half_float",
          "time_series_metric": "gauge"
        },
        "@timestamp": {
          "type": "date",
          "format": "strict_date_optional_time"
        }
      }
    }
  },
  "_meta": {
    "description": "Mappings for weather sensor data"
  }
}
----
// TEST[continued]

[discrete]
[[tsds-create-index-settings-component-template]]
==== Create an index settings component template

Optionally, the index settings component template for a TSDS can include:

* Your lifecycle policy in the `index.lifecycle.name` index setting.
* The <<tsds-look-ahead-time,`index.look_ahead_time`>> index setting.
* Other index settings, such as <<index-codec,`index.codec`>>, for your TSDS's
backing indices.

IMPORTANT: Don't specify the `index.routing_path` index setting in a component
template. If you choose, you can configure `index.routing_path` directly in the
index template, as shown in the following step.

[source,console]
----
PUT _component_template/my-weather-sensor-settings
{
  "template": {
    "settings": {
      "index.lifecycle.name": "my-lifecycle-policy",
      "index.look_ahead_time": "3h",
      "index.codec": "best_compression"
    }
  },
  "_meta": {
    "description": "Index settings for weather sensor data"
  }
}
----
// TEST[continued]

[discrete]
[[create-tsds-index-template]]
==== Create an index template

Use your component templates to create an index template. In the index template,
specify:

* One or more index patterns that match the TSDS's name. We recommend
using our {fleet-guide}/data-streams.html#data-streams-naming-scheme[data stream
naming scheme].

* That the template is data stream enabled.

* An `index.mode` object set to `time_series`.

* Optional: The `index.routing_path` index setting. The setting value should
only match plain `keyword` dimension fields and should be set directly in the
index template. When not defined explicitly, the `index.routing_path` setting is
generated from the mapping using all mappings that are set with
`time_series_dimension` set to `true`.

* The component templates containing your mappings and other index settings.

* A priority higher than `200` to avoid collisions with built-in templates.
See <<avoid-index-pattern-collisions>>.

[source,console]
----
PUT _index_template/my-weather-sensor-index-template
{
  "index_patterns": ["metrics-weather_sensors-*"],
  "data_stream": { },
  "template": {
    "settings": {
      "index.mode": "time_series",
      "index.routing_path": [ "sensor_id", "location" ]
    }
  },
  "composed_of": [ "my-weather-sensor-mappings", "my-weather-sensor-settings" ],
  "priority": 500,
  "_meta": {
    "description": "Template for my weather sensor data"
  }
}
----
// TEST[continued]

////
[source,console]
----
DELETE _data_stream/*
DELETE _index_template/*
DELETE _component_template/my-*
DELETE _ilm/policy/my-weather-sensor-lifecycle-policy
----
// TEST[continued]
////

[discrete]
[[create-tsds]]
==== Create the TSDS

<<add-documents-to-a-data-stream,Indexing requests>> add documents to a TSDS.
Documents in a TSDS must include:

* A `@timestamp` field
* One or more dimension fields. At least one dimension must be a `keyword` field
that matches the `index.routing_path` index setting, if specified. If not specified
explicitly, `index.routing_path` is set automatically to whichever mappings have
 `time_series_dimension` set to `true`.

To automatically create your TSDS, submit an indexing request that
targets the TSDS's name. This name must match one of your index template's
index patterns.

To test the following example, update the timestamps to within the 24 hours after
your current time.

[source,console]
----
PUT metrics-weather_sensors-dev/_bulk
{ "create":{ } }
{ "@timestamp": "2099-05-06T16:21:15.000Z", "sensor_id": "HAL-000001", "location": "plains", "temperature": 26.7,"humidity": 49.9 }
{ "create":{ } }
{ "@timestamp": "2099-05-06T16:25:42.000Z", "sensor_id": "SYKENET-000001", "location": "swamp", "temperature": 32.4, "humidity": 88.9 }

POST metrics-weather_sensors-dev/_doc
{
  "@timestamp": "2099-05-06T16:21:15.000Z",
  "sensor_id": "SYKENET-000001",
  "location": "swamp",
  "temperature": 32.4,
  "humidity": 88.9
}
----
// TEST[skip: The @timestamp value won't match an accepted range in the TSDS]

You can also manually create the TSDS using the
<<indices-create-data-stream,create data stream API>>. The TSDS's name must
still match one of your template's index patterns.

[source,console]
----
PUT _data_stream/metrics-weather_sensors-dev
----
// TEST[setup:tsds_template]
// TEST[teardown:tsds_cleanup]

[discrete]
[[secure-tsds]]
==== Secure the TSDS

Use <<privileges-list-indices,index privileges>> to control access to a TSDS.
Granting privileges on a TSDS grants the same privileges on its backing indices.

For an example, refer to <<data-stream-privileges>>.

[discrete]
[[convert-existing-data-stream-to-tsds]]
==== Convert an existing data stream to a TSDS

You can also use the above steps to convert an existing regular data stream to
a TSDS. In this case, you'll want to:

* Edit your existing index lifecycle policy, component templates, and index
templates instead of creating new ones.

* Instead of creating the TSDS, manually roll over its write index. This ensures
the current write index and any new backing indices have an
<<time-series-mode,`index.mode` of `time_series`>>.
+
You can manually roll over the write index using the
<<indices-rollover-index,rollover API>>.
+
[source,console]
----
POST metrics-weather_sensors-dev/_rollover
----
// TEST[setup:tsds]
// TEST[teardown:tsds_cleanup]

[discrete]
[[set-up-tsds-whats-next]]
==== What's next?

Now that you've set up your TSDS, you can manage and use it like a regular
data stream. For more information, refer to:

* <<use-a-data-stream>>
* <<data-streams-change-mappings-and-settings>>
* <<data-stream-apis,data stream APIs>>