[role="xpack"]
[testenv="platinum"]
[[start-dfanalytics]]
=== Start {dfanalytics-jobs} API

[subs="attributes"]
++++
<titleabbrev>Start {dfanalytics-jobs}</titleabbrev>
++++

Starts a {dfanalytics-job}.

experimental[]

[[ml-start-dfanalytics-request]]
==== {api-request-title}

`POST _ml/data_frame/analytics/<data_frame_analytics_id>/_start`

[[ml-start-dfanalytics-prereq]]
==== {api-prereq-title}

If the {es} {security-features} are enabled, you must have the following built-in roles and privileges:

* `machine_learning_admin`
* `kibana_admin` (UI only)

* source indices: `read`, `view_index_metadata`
* destination index: `read`, `create_index`, `manage` and `index`
* cluster: `monitor` (UI only)
  
For more information, see <<security-privileges>> and <<built-in-roles>>.

[[ml-start-dfanalytics-desc]]
==== {api-description-title}

A {dfanalytics-job} can be started and stopped multiple times throughout its 
lifecycle.

If the destination index does not exist, it is created automatically the first
time you start the {dfanalytics-job}. The `index.number_of_shards` and
`index.number_of_replicas` settings for the destination index are copied from
the source index. If there are multiple source indices, the destination index
copies the highest setting values. The mappings for the destination index are
also copied from the source indices. If there are any mapping conflicts, the job
fails to start.

If the destination index exists, it is used as is. You can therefore set up the
destination index in advance with custom settings and mappings.

[[ml-start-dfanalytics-path-params]]
==== {api-path-parms-title}

`<data_frame_analytics_id>`::
(Required, string)
include::{docdir}/ml/ml-shared.asciidoc[tag=job-id-data-frame-analytics-define]

[[ml-start-dfanalytics-query-params]]
==== {api-query-parms-title}

`timeout`::
(Optional, <<time-units,time units>>) 
include::{docdir}/ml/ml-shared.asciidoc[tag=timeout-start]

[[ml-start-dfanalytics-example]]
==== {api-examples-title}

The following example starts the `loganalytics` {dfanalytics-job}:

[source,console]
--------------------------------------------------
POST _ml/data_frame/analytics/loganalytics/_start
--------------------------------------------------
// TEST[skip:setup:logdata_job]

When the {dfanalytics-job} starts, you receive the following results:

[source,console-result]
----
{
  "acknowledged" : true
}
----