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.

The BMS OS-EXT-STS:vm_state attribute (BMS status) must be active, stopped, paused, or suspended.

POST /v2.1/{project_id}/servers/{server_id}/metadata

Table 1 lists the parameters.

**Table 1** Parameter description
Parameter	Mandatory	Description
project_id	Yes	Specifies the project ID. For how to obtain the project ID, see Obtaining Required Information.
server_id	Yes	Specifies the BMS ID. You can obtain the BMS ID from the BMS console or using the Querying BMSs (Native OpenStack API) API.

Request parameters

Parameter	Mandatory	Type	Description
metadata	Yes	Object	Specifies the user-defined metadata key and value pair. For details, see Table 2.

**Table 2** **metadata** field data structure description
Parameter	Mandatory	Type	Description
User-defined field key and value pair	Yes	String	Specifies the user-defined metadata key and value pair. Each key or value contains a maximum of 255 characters. The key does not support the following special characters: :`~!@#$%^&*()=+<,>?/'";{[]}\|\ The value does not support the following special characters: \"

Example request

POST https://{ECS Endpoint}/v2.1/c685484a8cc2416b97260938705deb65/servers/95bf2490-5428-432c-ad9b-5e3406f869dd/metadata

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

Response parameters

Parameter	Type	Description
metadata	Object	Specifies the user-defined metadata key and value pair. For details, see Table 3.

**Table 3** **metadata** field data structure description
Parameter	Type	Description
User-defined field key and value pair	String	Specifies the key and value pair of the metadata. Each key or value contains a maximum of 255 characters. The value does not support the following special 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 (Native OpenStack API)