nova/doc/api_samples/os-floating-ip-dns/floating-ip-dns-create-or-update-entry-resp.json

{
    "dns_entry": {
        "domain": "domain1.example.org",
        "id": null,
        "ip": "192.168.1.1",
        "name": "instance1",
        "type": "A"
    }
}