# Querying Information About Disks Attached to an ECS

#### Function

This API is used to query information about disks attached to an ECS.

#### URI

GET /v1/{project_id}/cloudservers/{server_id}/block_device

Table 1 describes the parameters in the URI.

Table 1 Parameter description
Parameter | Mandatory | Description
--- | --- | ---
project_id | Yes | Specifies the project ID.
server_id | Yes | Specifies the ECS ID in UUID format.

#### Request

None

#### Response

Table 2 describes the response parameters.

Table 2 Response parameters
Parameter | Type | Description
--- | --- | ---
volumeAttachments | Array of objects | Specifies the disks attached to an ECS. For details, see Table 3.
attachableQuantity | Object | Specifies the number of disks that can be attached to an ECS. For details, see Table 4.

Table 3 volumeAttachments parameters
Parameter | Type | Description
--- | --- | ---
serverId | String | Specifies the ECS ID in UUID format.
volumeId | String | Specifies the EVS disk ID in UUID format.
id | String | Specifies the mount ID, which is the same as the EVS disk ID. The value is in UUID format.
size | Integer | Specifies the EVS disk size in GB.
device | String | Specifies the drive letter of the EVS disk, which is the device name of the EVS disk.
pciAddress | String | Specifies the PCI address.

bootIndex

Integer

Specifies the EVS disk boot sequence.

- 0 indicates the system disk.
- Non-0 indicates a data disk.

bus | String | Specifies the disk bus type. Options: virtio and scsi

Table 4 attachableQuantity parameters
Parameter | Type | Description
--- | --- | ---
free_scsi | Integer | Specifies the number of SCSI disks that can be attached to an ECS.
free_blk | Integer | Specifies the number of virtio_blk disks that can be attached to an ECS.
free_disk | Integer | Specifies the total number of disks that can be attached to an ECS.

#### Example Request

    GET https://{endpoint}/v1/{project_id}/cloudservers/{server_id}/block_device

#### Example Response

    {
        "attachableQuantity": {
                "free_scsi": 23,
                "free_blk": 15,
                "free_disk": 23
         },
        "volumeAttachments": [
            {
                "pciAddress": "0000:02:01.0",
                "volumeId": "a26887c6-c47b-4654-abb5-dfadf7d3f803",
                "device": "/dev/vda",
                "serverId": "4d8c3732-a248-40ed-bebc-539a6ffd25c0",
                "id": "a26887c6-c47b-4654-abb5-dfadf7d3f803",
                "size": "40",
                "bootIndex": 0,
                "bus":"virtio"
            },
            {
                "pciAddress": "0000:02:02.0",
                "volumeId": "a26887c6-c47b-4654-abb5-asdf234r234r",
                "device": "/dev/vdb",
                "serverId": "4d8c3732-a248-40ed-bebc-539a6ffd25c0",
                "id": "a26887c6-c47b-4654-abb5-asdf234r234r",
                "size": "10",
                "bootIndex": 1,
                "bus":"virtio"
            }
        ]
    }

#### Returned Values

See Returned Values for General Requests.

#### Error Codes

See Error Codes.

Parent topic: Disk Management