## POST /api/v2/volumes/{id}/actions/attach

**Attach block volume**

Attach an available block volume to a VPS. Get volume `{id}` from `GET /api/v2/volumes`, and get `vpsId` from `GET /api/v2/vps`. `diskSlot` is optional and defaults to `scsi1`; allowed slots are `scsi1` through `scsi6`.

### Related Endpoints

- `POST /api/v2/volumes/{id}/actions/detach`: Detach block volume
- `GET /api/v2/volumes/{id}`: Get block volume
- `DELETE /api/v2/volumes/{id}`: Delete block volume

### Headers

- `Accept`: application/json
- `Authorization`: Bearer YOUR_API_KEY
- Required API scopes: `write:vm`, `write:storage`
- `Content-Type`: application/json

### Parameters

- `id` (path, string, required): Public volume ID. Get it from GET /api/v2/volumes `data[].id`. Do not invent this value; use the exact ID returned by the referenced API response. Example: `vol_01hxa3b4c5d6e7f8g9h0j1k2m3`

### Request Body

- `vpsId` (string, required) Example: `vps_01hxa3b4c5d6e7f8g9h0j1k2m3`
- `diskSlot` (string, optional) Example: `scsi1`
  Allowed values: scsi1, scsi2, scsi3, scsi4, scsi5, scsi6

### Request Examples

#### Attach to VPS

```bash
curl -X POST "https://cloud.hostup.se/api/v2/volumes/vol_01hxa3b4c5d6e7f8g9h0j1k2m3/actions/attach" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Accept: application/json" \
  -H "Content-Type: application/json" \
  -d '{
    "vpsId": "vps_01hxa3b4c5d6e7f8g9h0j1k2m3",
    "diskSlot": "scsi1"
  }'
```

```json
{
  "vpsId": "vps_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "diskSlot": "scsi1"
}
```

### Response Schema

- `operation` (object, required)
- `operation.status` (string, required) Example: `queued`
  Allowed values: queued, pending, in_progress
- `operation.jobId` (string,null, required) Example: `job_01hxa3b4c5d6e7f8g9h0j1k2m3`
- `operation.pollUrl` (string,null, required) Example: `/api/jobs/job_01hxa3b4c5d6e7f8g9h0j1k2m3`

### Responses

#### 202 - Attach operation queued.
```json
{
  "operation": {
    "status": "queued",
    "jobId": "job_01hxa3b4c5d6e7f8g9h0j1k2m3",
    "pollUrl": "/api/jobs/job_01hxa3b4c5d6e7f8g9h0j1k2m3"
  }
}
```

#### 400 - Invalid request. The response body is an RFC 7807 Problem Details document.
```json
{
  "type": "https://developer.hostup.se/errors/invalid_request",
  "title": "Invalid request",
  "status": 400,
  "detail": "The request body failed validation.",
  "code": "invalid_request",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z",
  "errors": [
    {
      "pointer": "/items/0/domainName",
      "detail": "`domainName` is required.",
      "code": "invalid_request"
    }
  ]
}
```

#### 401 - Unauthorized. Authentication is required.
```json
{
  "type": "https://developer.hostup.se/errors/unauthorized",
  "title": "Unauthorized",
  "status": 401,
  "detail": "Authentication is required.",
  "code": "unauthorized",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```

#### 403 - Forbidden. The caller lacks a required scope or does not own the resource.
```json
{
  "type": "https://developer.hostup.se/errors/forbidden",
  "title": "Forbidden",
  "status": 403,
  "detail": "The caller lacks a required scope or does not own the resource.",
  "code": "forbidden",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```

#### 404 - Not found. The resource does not exist or is not owned by the caller.
```json
{
  "type": "https://developer.hostup.se/errors/not_found",
  "title": "Not found",
  "status": 404,
  "detail": "The requested resource could not be found.",
  "code": "not_found",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```

#### 429 - Rate limited. Retry after the limit resets. 429 responses include `Retry-After` seconds plus `X-RateLimit-*` headers.
```json
{
  "type": "https://developer.hostup.se/errors/rate_limit_exceeded",
  "title": "Too many requests",
  "status": 429,
  "detail": "Too many requests. Retry after the limit resets.",
  "code": "rate_limit_exceeded",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```

#### 500 - Internal error. Retry later or contact support if the issue persists.
```json
{
  "type": "https://developer.hostup.se/errors/internal_error",
  "title": "Internal server error",
  "status": 500,
  "detail": "An unexpected error occurred. Retry later or contact support if the issue persists.",
  "code": "internal_error",
  "instance": "/api/v2/resource",
  "requestId": "req_01hxa3b4c5d6e7f8g9h0j1k2m3",
  "timestamp": "2026-04-27T12:34:56.000Z"
}
```