nova/doc/api_samples/os-volumes/attach-volume-to-server-resp.json

{
    "volumeAttachment": {
        "device": "/dev/vdd",
        "id": "a26887c6-c47b-4654-abb5-dfadf7d3f803",
        "serverId": "0c92f3f6-c253-4c9b-bd43-e880a8d2eb0a",
        "volumeId": "a26887c6-c47b-4654-abb5-dfadf7d3f803"
    }
}