[[ml-revert-snapshot]]
==== Update Model Snapshots

The update model snapshot API allows you to update certain properties of a snapshot.

===== Request

`POST _xpack/ml/anomaly_detectors/<job_id>/model_snapshots/<snapshot_id>/_update`

////
===== Description

Important:: Updates do not take effect until after then job is closed and new
data is sent to it.
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===== Path Parameters

`job_id` (required)::
  (+string+) Identifier for the job

`snapshot_id` (required)::
  (+string+) Identifier for the model snapshot

===== Request Body

The following properties can be updated after the job is created:

TBD

////
`analysis_config`::
  (+object+) The analysis configuration, which specifies how to analyze the data.
  See <<ml-analysisconfig, analysis configuration objects>>.  In particular, the following properties can be updated: `categorization_filters`, `detector_description`, TBD.

`analysis_limits`::
  Optionally specifies runtime limits for the job. See <<ml-apilimits,analysis limits>>.

[NOTE]
* You can update the `analysis_limits` only while the job is closed.
* The `model_memory_limit` property value cannot be decreased.
* If the `memory_status` property in the `model_size_stats` object has a value of `hard_limit`,
increasing the `model_memory_limit` is not recommended.

`description`::
  (+string+) An optional description of the job.


This expects data to be sent in JSON format using the POST `_data` API.

===== Responses

TBD
200
(EmptyResponse) The cluster has been successfully deleted
404
(BasicFailedReply) The cluster specified by {cluster_id} cannot be found (code: clusters.cluster_not_found)
412
(BasicFailedReply) The Elasticsearch cluster has not been shutdown yet (code: clusters.cluster_plan_state_error)


===== Examples

The following example updates the `it-ops-kpi` job:

[source,js]
--------------------------------------------------
PUT _xpack/ml/anomaly_detectors/it-ops-kpi/_update
{
    "description":"New description",
    "analysis_limits":{
      "model_memory_limit": 8192
    }
}
--------------------------------------------------
// CONSOLE
// TEST[skip:todo]

When the job is updated, you receive the following results:
----
{
  "job_id": "it-ops-kpi",
  "description": "New description",
  ...
  "analysis_limits": {
    "model_memory_limit": 8192
  ...
}
----
////