This API is used to update BMS metadata.

If the metadata does not contain the target field, the field is automatically added to the field.
If the metadata contains the target field, the field value is automatically updated.
If the field in the metadata is not requested, the field value remains unchanged.

The BMS must be in active, stopped, or paused state. The state is indicated by the OS-EXT-STS:vm_state parameter.

POST /v1/{project_id}/baremetalservers/{server_id}/metadata

Table 1 lists the parameters.

**Table 1** Parameter description
Parameter	Mandatory	Description
project_id	Yes	Specifies the project ID. For details about how to obtain the project ID, see Obtaining a Project ID.
server_id	Yes	Specifies the BMS ID. You can obtain the BMS ID from the BMS console or by calling the Querying BMSs (Native OpenStack API).

**Table 2** Request parameters
Parameter	Mandatory	Type	Description
metadata	Yes	Object	Specifies the user-defined metadata key-value pair. If you do not specify any key-value pair, metadata will not be updated. key: It contains a maximum of 255 Unicode characters which can be letters, digits, hyphens (-), underscores (_), colons (:), and periods (.). key cannot be left blank. value: It contains a maximum of 255 Unicode characters.

Example request

POST https://{BMS Endpoint}/v1/bbf1946d374b44a0a2a95533562ba954/baremetalservers/cf2a8b97-b5c6-47ef-9714-eb27adf26e5b/metadata

{
    "metadata": {
        "key": "value"
    }
}

**Table 3** Parameter description
Parameter	Mandatory	Type	Description
metadata	Yes	Object	Specifies the user-defined metadata key-value pair. If you do not specify any key-value pair, metadata will not be updated. key: It contains a maximum of 255 Unicode characters which can be letters, digits, hyphens (-), underscores (_), colons (:), and periods (.). key cannot be left blank. value: It contains a maximum of 255 Unicode characters.

Example response

{
    "metadata":{
        "key": "value"
    }
} 

Normal values

Returned Values	Description
200	The request has been successfully processed.

For details about other returned values, see Status Codes.

Updating BMS Metadata