# Create a NAT Gateway Rule

Create a NAT gateway rule to configure Source NAT (SNAT) behavior for your private network traffic using the `POST` request. The rules determine which private IP addresses can access the Internet through the NAT gateway.

{% hint style="info" %}
**Rule specifications:** Define a name, protocol (`TCP`, `UDP`, `ICMP`, `ESP`, `AH`, or `GRE`), source subnet, and target subnet for each rule. You can also optionally specify a target port range.
{% endhint %}

## Endpoint

`https://api.ionos.com/cloudapi/v6/datacenters/{datacenterId}/natgateways/{natGatewayId}/rules`

## Request

```bash
curl --location \
--request POST 'https://api.ionos.com/cloudapi/v6/datacenters/15f67991-0f51-4efc-a8ad-ef1fb31a480c/natgateways/d8fbc490-3b3e-4f7a-b6e1-2c8d5f3e7a9b/rules' \
--header 'Authorization: Bearer $IONOS_TOKEN' \
--header 'Content-Type: application/json' \
--data-raw '{
  "properties": {
    "name": "Web Traffic Rule",
    "protocol": "TCP",
    "publicIp": "203.0.113.50",
    "sourceSubnet": "10.0.1.0/24",
    "targetSubnet": "0.0.0.0/0",
    "targetPortRange": {
      "start": 80,
      "end": 443
    },
    "type": "SNAT"
  }
}'
```

{% tabs %}
{% tab title="Request Body Parameters" %}
The following table lists the request body parameters:

| **Body Parameters**                | **Required** | **Type** | **Description**                                                                                                 | **Example**            |
| ---------------------------------- | ------------ | -------- | --------------------------------------------------------------------------------------------------------------- | ---------------------- |
| `properties.name`                  | yes          | string   | The name of the NAT gateway rule.                                                                               | `Web Traffic Rule`     |
| `properties.protocol`              | no           | string   | The network protocol for the rule. If you do not specify a protocol, the system allows all supported protocols. | `TCP`                  |
| `properties.publicIp`              | yes          | string   | The public IP address that the NAT gateway uses for the specific rule.                                          | `203.0.113.50`         |
| `properties.sourceSubnet`          | yes          | string   | The source subnet in CIDR notation.                                                                             | `10.0.1.0/24`          |
| `properties.targetSubnet`          | no           | string   | The target or destination subnet in CIDR notation.                                                              | `0.0.0.0/0`            |
| `properties.targetPortRange`       | no           | object   | The port range for the target subnet.                                                                           | See nested properties. |
| `properties.targetPortRange.start` | no           | integer  | The starting port of the range.                                                                                 | `80`                   |
| `properties.targetPortRange.end`   | no           | integer  | The ending port of the range.                                                                                   | `443`                  |
| `properties.type`                  | no           | string   | The type of NAT gateway rule.                                                                                   | `SNAT`                 |
| {% endtab %}                       |              |          |                                                                                                                 |                        |

{% tab title="Request Header Parameters" %}
Include the following mandatory fields in the request header to authenticate your requests:

| **Header Parameters** | **Required** | **Type** | **Description**                                                             |
| --------------------- | ------------ | -------- | --------------------------------------------------------------------------- |
| `Authorization`       | yes          | string   | Use a Bearer token to authenticate requests through a JSON Web Token (JWT). |
| `Content-Type`        | yes          | string   | Set it to `application/json`.                                               |
| {% endtab %}          |              |          |                                                                             |
| {% endtabs %}         |              |          |                                                                             |

## Response

A **202 Accepted** response indicates that the NAT Gateway rule is successfully created. The `id` and other details are provided in the response.

{% hint style="info" %}
**Note:** NAT Gateway rule creation is performed asynchronously. The resource maintains a `BUSY` status until provisioning completes. The response includes a `Location` header with a URL to poll the request status.
{% endhint %}

```json
{
  "id": "a7f2e4d8-9c3b-4f6a-b5e8-1d2c3f4a5b6c",
  "type": "nat-gateway-rule",
  "href": "/cloudapi/v6/datacenters/15f67991-0f51-4efc-a8ad-ef1fb31a480c/natgateways/d8fbc490-3b3e-4f7a-b6e1-2c8d5f3e7a9b/rules/a7f2e4d8-9c3b-4f6a-b5e8-1d2c3f4a5b6c",
  "metadata": {
    "etag": "45480eb3fbfc31f1d916c1eaa4abdcc3",
    "createdDate": "2024-01-15T13:45:30+00:00",
    "createdBy": "ionos:identity:::users/87f9d82e-b28d-49ed-9d04-fba2c0459cd3",
    "createdByUserId": "87f9d82e-b28d-49ed-9d04-fba2c0459cd3",
    "lastModifiedDate": "2024-01-15T13:45:30+00:00",
    "lastModifiedBy": "ionos:identity:::users/87f9d82e-b28d-49ed-9d04-fba2c0459cd3",
    "lastModifiedByUserId": "87f9d82e-b28d-49ed-9d04-fba2c0459cd3",
    "state": "BUSY"
  },
  "properties": {
    "name": "Web Traffic Rule",
    "protocol": "TCP",
    "publicIp": "203.0.113.50",
    "sourceSubnet": "10.0.1.0/24",
    "targetSubnet": "0.0.0.0/0",
    "targetPortRange": {
      "start": 80,
      "end": 443
    },
    "type": "SNAT"
  }
}
```


---

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