Use the snapshot management (SM) API to automate [taking snapshots]({{site.url}}{{site.baseurl}}/opensearch/snapshots/snapshot-restore#take-snapshots).
`snapshot_config.date_format` | String | Snapshot names have the format `<policy_name>-<date>-<random number>`. `date_format` specifies the format for the date in the snapshot name. Supports all date formats supported by OpenSearch. Optional. Default is "yyyy-MM-dd'T'HH:mm:ss".
`snapshot_config.date_format_timezone` | String | Snapshot names have the format `<policy_name>-<date>-<random number>`. `date_format_timezone` specifies the time zone for the date in the snapshot name. Optional. Default is UTC.
`snapshot_config.indices` | String | The names of the indexes in the snapshot. Multiple index names are separated by `,`. Supports wildcards (`*`). Optional. Default is `*` (all indexes).
`snapshot_config.repository` | String | The repository in which to store snapshots. Required.
`snapshot_config.ignore_unavailable` | Boolean | Do you want to ignore unavailable indexes? Optional. Default is `false`.
`snapshot_config.include_global_state` | Boolean | Do you want to include cluster state? Optional. Default is `true` because of [Security plugin considerations]({{site.url}}{{site.baseurl}}/tuning-your-cluster/availability-and-recovery/snapshots/snapshot-restore#security-considerations).
`creation.schedule` | String | The cron schedule used to create snapshots. Required.
`creation.time_limit` | String | Sets the maximum time to wait for snapshot creation to finish. If time_limit is longer than the scheduled time interval for taking snapshots, no scheduled snapshots are taken until time_limit elapses. For example, if time_limit is set to 35 minutes and snapshots are taken every 30 minutes starting at midnight, the snapshots at 00:00 and 01:00 are taken, but the snapshot at 00:30 is skipped. Optional.
`notification.channel` | Object | Defines a channel for notifications. You must [create and configure a notification channel]({{site.url}}{{site.baseurl}}/notifications-plugin/api) before setting up SM notifications. Required.
`notification.channel.id` | String | The channel ID of the channel used for notifications. To get the channel IDs of all created channels, use `GET _plugins/_notifications/configs`. Required.
`notification.conditions` | Object | SM events you want to be notified about. Set the ones you are interested in to `true`.
`notification.conditions.creation` | Boolean | Do you want notifications about snapshot creation? Optional. Default is `true`.
`notification.conditions.deletion` | Boolean | Do you want notifications about snapshot deletion? Optional. Default is `false`.
`notification.conditions.failure` | Boolean | Do you want notifications about creation or deletion failure? Optional. Default is `false`.
`notification.conditions.time_limit_exceeded` | Boolean | Do you want notifications when snapshot operations take longer than time_limit? Optional. Default is `false`.
You can use a [query string]({{site.url}}{{site.baseurl}}/opensearch/query-dsl/full-text/index#query-string) and specify pagination, the field to be sorted by, and sort order:
GET _plugins/_sm/policies?from=0&size=20&sortField=sm_policy.name&sortOrder=desc&queryString=*
```
Get a specific SM policy:
```
GET _plugins/_sm/policies/<policy_name>
```
### Example
```json
GET _plugins/_sm/policies/daily-policy
```
### Response
```json
{
"_id" : "daily-policy-sm-policy",
"_version" : 6,
"_seq_no" : 44696,
"_primary_term" : 19,
"sm_policy" : {
"name" : "daily-policy",
"description" : "Daily snapshot policy",
"schema_version" : 15,
"creation" : {
"schedule" : {
"cron" : {
"expression" : "0 8 * * *",
"timezone" : "UTC"
}
},
"time_limit" : "1h"
},
"deletion" : {
"schedule" : {
"cron" : {
"expression" : "0 1 * * *",
"timezone" : "America/Los_Angeles"
}
},
"condition" : {
"max_age" : "7d",
"min_count" : 7,
"max_count" : 21
},
"time_limit" : "1h"
},
"snapshot_config" : {
"metadata" : {
"any_key" : "any_value"
},
"ignore_unavailable" : "true",
"include_global_state" : "false",
"date_format" : "yyyy-MM-dd-HH:mm",
"repository" : "s3-repo",
"partial" : "true"
},
"schedule" : {
"interval" : {
"start_time" : 1656341042874,
"period" : 1,
"unit" : "Minutes"
}
},
"enabled" : true,
"last_updated_time" : 1656341042874,
"enabled_time" : 1656341042874
}
}
```
## Explain
Introduced 2.1
{: .label .label-purple }
Provides the enabled/disabled status and the metadata for all policies specified. Multiple policy names are separated with `,`. You can also specify desired policies with a wildcard pattern.
<imgsrc="{{site.url}}{{site.baseurl}}/images/sm-state-machine.png"alt="SM State Machine"width="150"style="float: left; margin-right: 15px;"/>
SM uses a state machine for snapshot creation and deletion. The image on the left shows one execution period of the creation workflow, from the CREATION_START state to the CREATION_FINISHED state. Deletion workflow follows the same pattern as creation workflow.
The creation workflow starts in the CREATION_START state and continuously checks if the conditions in the creation cron schedule are met. After the conditions are met, the creation workflow switches to the CREATION_CONDITION_MET state and continues to the CREATING state. The CREATING state calls the create snapshot API asynchronously and then waits for snapshot creation to end in the CREATION_FINISHED state. Once snapshot creation ends, the creation workflow goes back to the CREATION_START state, and the cycle continues. The `current_state` field of `metadata.creation` and `metadata.deletion` returns the current state of the state machine.
#### Request
```json
GET _plugins/_sm/policies/<policy_names>/_explain
```
### Example
```json
GET _plugins/_sm/policies/daily*/_explain
```
### Response
```json
{
"policies" : [
{
"name" : "daily-policy",
"creation" : {
"current_state" : "CREATION_START",
"trigger" : {
"time" : 1656403200000
}
},
"deletion" : {
"current_state" : "DELETION_START",
"trigger" : {
"time" : 1656403200000
}
},
"policy_seq_no" : 44696,
"policy_primary_term" : 19,
"enabled" : true
}
]
}
```
The following table lists all fields for each policy in the response.
Field | Description
:--- |:---
`name` | The name of the SM policy.
`creation` | Information about the latest creation operation. See subfields below.
`deletion` | Information about the latest deletion operation. See subfields below.
`policy_seq_no`<br>`policy_primary_term` | The version of the SM policy.
`enabled` | Is the policy running?
The following table lists all fields in the `creation` and `deletion` objects of each policy.
Field | Description
:--- |:---
`current_state` | The current state of the state machine that runs snapshot creation/deletion as described above.
`trigger.time` | The next creation/deletion execution time in milliseconds since the epoch.
`latest_execution` | Describes the latest creation/deletion execution.
`latest_execution.status` | The execution status of the latest creation/deletion. Possible values are:<br>`IN_PROGRESS`: Snapshot creation/deletion has started. <br>`SUCCESS`: Snapshot creation/deletion has finished successfully. <br>`RETRYING`: The creation/deletion attempt has failed. It will be retried three times. <br>`FAILED`: The creation/deletion attempt failed after three retries. End the current execution period and go to the next execution period. <br>`TIME_LIMIT_EXCEEDED`: The creation/deletion time exceeded the time_limit set in the policy. End the current execution period and go to the next execution period.
`latest_execution.start_time` | The start time of the latest execution in milliseconds since the epoch.
`latest_execution.end_time` | The end time of the latest execution in milliseconds since the epoch.
`latest_execution.info.message` | A user-friendly message describing the status of the latest execution.
`latest_execution.info.cause` | Contains the failure reason if the latest execution fails.
`retry.count` | The number of remaining execution retry attempts.
## Start a policy
Introduced 2.1
{: .label .label-purple }
Starts the policy by setting its `enabled` flag to `true`.
#### Request
```json
POST _plugins/_sm/policies/<policy_name>/_start
```
### Example
```json
POST _plugins/_sm/policies/daily-policy/_start
```
### Response
```json
{
"acknowledged" : true
}
```
## Stop a policy
Introduced 2.1
{: .label .label-purple }
Sets the `enabled` flag to `false` for an SM policy. The policy will not run until you [start](#start-a-policy) it.
