# ModifyInstanceBandwidth

## 1. API Description

This API (ModifyInstanceBandwidth) is used to the API is used to modify the public bandwidth of a virtual machine instance.

{% hint style="info" %} <mark style="color:blue;">**Note**</mark>

* <mark style="color:blue;">You can only perform this operation on instances whose status is</mark> <mark style="color:blue;">`RUNNING`</mark><mark style="color:blue;">.</mark>
* <mark style="color:blue;">If the</mark> [<mark style="color:purple;">`internetChargeType`</mark>](/api-reference/compute/vm/datastructure.md#internetchargetype) <mark style="color:blue;">of your instance is</mark> <mark style="color:blue;">`ByBandwidth`</mark>
  * <mark style="color:blue;">For a</mark> <mark style="color:blue;">`PREPAID`</mark> <mark style="color:blue;">instance:</mark>
    * <mark style="color:blue;">Upgrade (target > current) operation will deduct the amount required for this instance purchase. If the balance is insufficient, the request will fail and take effect immediately.</mark>
    * <mark style="color:blue;">Downgrade (target < current) operation will generate an order for the next billing cycle and will take effect by then.</mark>
  * <mark style="color:blue;">For a</mark> <mark style="color:blue;">`POSTPAID`</mark> <mark style="color:blue;">instance, the change takes immediate effect.</mark>
* <mark style="color:blue;">If the</mark> [<mark style="color:purple;">`internetChargeType`</mark>](/api-reference/compute/vm/datastructure.md#internetchargetype) <mark style="color:blue;">of your instance is not</mark> <mark style="color:blue;">`ByBandwidth`</mark>, <mark style="color:blue;">the bandwidth change takes immediate effect.</mark>
* <mark style="color:blue;">This API is an async API. Use</mark> <mark style="color:blue;">`DescribeInstanceInternetStatus`</mark> <mark style="color:blue;">to query bandwidth status of an instance.</mark>
  {% endhint %}

## 2. Input Parameters

The following request parameter list only provides API request parameters.

| Parameter Name          | Required | Type    | Description                                                                                                                      |
| ----------------------- | -------- | ------- | -------------------------------------------------------------------------------------------------------------------------------- |
| instanceId              | Yes      | String  | <p>Instance ID(s).</p><p>To obtain the instance IDs, you can call DescribeInstances and look for instanceId in the response.</p> |
| internetMaxBandwidthOut | Yes      | Integer | <p>Egress bandwidth size.</p><p>Valid value: ≥1.</p><p>Value range: \[1, +)</p>                                                  |

## 3. Output Parameters

| Parameter Name | Type   | Description                                                                                                           |
| -------------- | ------ | --------------------------------------------------------------------------------------------------------------------- |
| requestId      | String | <p>The unique request ID, which is returned for each request.</p><p>RequestId is required for locating a problem.</p> |
| orderNumber    | String | Number of order.                                                                                                      |

## 4. Code Example

{% tabs %}
{% tab title="Example" %}
**Upgrade instance bandwidth.**

```javascript
POST /api/v2/vm HTTP/1.1
Host: console.zenlayer.com
Content-Type: application/json
X-ZC-Action: ModifyInstanceBandwidth
<Common Request Params>

Request：
{
  "instanceId": "instanceId",
  "internetMaxBandwidthOut": 100
}

Response：
{
  "requestId": "T05992D0C-7E8B-4047-B0C0-780F2CD549D3",
  "response": {  
    "requestId": "T05992D0C-7E8B-4047-B0C0-780F2CD549D3",
    "orderNumber": "xxxx"
  }
}
```

{% endtab %}
{% endtabs %}

## 5. Developer Resources

Zenlayer Cloud API 2.0 integrates [SDKs](/api-reference/api-introduction/toolkit/api-sdk.md)，to make it easier for you to call APIs. More programming languages will be supported.

## 6. Error Codes

The following only lists the error codes related to the API business logic. For other error codes, see [Common Error Codes](/api-reference/api-introduction/instruction/commonerrorcode.md).

| HTTP Status Code | Error Code | Description |
| ---------------- | ---------- | ----------- |


---

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