> For the complete documentation index, see [llms.txt](https://docs.console.zenlayer.com/api-reference/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.console.zenlayer.com/api-reference/ipt/ip-transit/modifyiptransitconfig.md).
# ModifyIPTransitConfig
## 1. API Description
This API (ModifyIPTransitConfig) is used to modifies IP Transit configuration.
{% hint style="info" %}
**Notes**
* Configuration changes can only be made when the IP Transit state is **AVAILABLE**.
* This is an asynchronous API. After the request succeeds, the IP Transit state changes to **UPDATING**. You can poll the state via [DescribeIPTransits](https://github.com/zenlayer/zenlayercloud-api-doc-en/tree/main/ipt/ip-transit/describe-iptransits.md); when it changes back to **AVAILABLE**, the change has succeeded.
* No other operations are allowed on this IP Transit during the change.
* **About type:**
* `BANDWIDTH`: Modifies the bandwidth cap. Requires `bandwidth`. You can pass `commitBandwidth` to set the committed bandwidth; otherwise, it defaults to the same value as the bandwidth cap. Under 95th percentile billing (`internetType=ByInstanceBandwidth95`), `bandwidth` must be greater than or equal to the effective committed bandwidth; otherwise the `INVALID_RIPT_BANDWIDTH_LESS_THAN_COMMIT` error is returned.
* `BFD`: Modifies the BFD configuration. Requires `bfd`. Pass `null` to disable BFD. BFD cannot be disabled for a high-availability IP Transit: passing `null` or an incomplete `bfd` returns the `OPERATION_DENIED_HA_BFD_DISABLE` error.
* `BGP_ROUTE_TYPE`: Modifies the BGP inbound route type. Requires `bgp.routeType`. Supported only for IP Transits with BGP routing; otherwise the `INVALID_RIPT_ROUTING_TYPE_NOT_BGP` error is returned.
* `BGP_ASN_AS_SET`: Modifies the allowed ASN/AS-SET list for BGP. `asn` cannot be modified after creation. You must provide either `asnList` or `asSetList` in `bgp`; otherwise the `INVALID_RIPT_BGP_ASN_LIST_MISSING` error is returned. Supported only for IP Transits with BGP routing; otherwise the `INVALID_RIPT_ROUTING_TYPE_NOT_BGP` error is returned.
* `BGP_PASSWORD`: Modifies the BGP MD5 password. Requires `bgp.password`. Supported only for IP Transits with BGP routing; otherwise the `INVALID_RIPT_ROUTING_TYPE_NOT_BGP` error is returned.
* `ADD_CIDR_BLOCK`: Adds a public IPv4 CIDR block. Requires `publicIPv4BlockSize`. You can optionally pass `ipNetworkType`, which defaults to `BGP_IP`. You can optionally pass `marketingInfo.usePocVoucher=true` to use a POC voucher; if no POC voucher is available in the system, the order will fail. Not supported for IP Transits with the Standard BGP tier (`bgp.tier=STANDARD`); otherwise the `OPERATION_DENIED_STANDARD_BGP_ADD_CIDR` error is returned.
* `DEL_CIDR_BLOCK`: Deletes a public IPv4 CIDR block. Requires `ipUuid`.
* `EXPAND_CIDR_BLOCK`: Expands an existing CIDR block (smaller netmask). Requires `ipUuid` and `publicIPv4BlockSize`. The target netmask cannot be smaller than the minimum netmask that the IP block can actually be expanded to at the underlying layer; otherwise the `OPERATION_DENIED_INVALID_CIDR_SIZE` error is returned.
* `SHRINK_CIDR_BLOCK`: Shrinks an existing CIDR block (larger netmask). Requires `ipUuid` and `publicIPv4BlockSize`. The target netmask likewise cannot be smaller than the minimum netmask that the IP block can actually be expanded to at the underlying layer.
* `HA_SWITCH_PRIMARY`: HA primary/secondary switchover. Available only for HA-mode IP Transits.
* `HA_SWITCH_MODE`: Switches the HA mode (active/standby ↔ active/active). Available only for HA-mode IP Transits.
{% endhint %}
## 2. Input Parameters
The following request parameter list only provides API request parameters.
| Parameter Name | Required | Type | Description |
| ------------------- | -------- | ------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| iptId | Yes | String | IP Transit instance ID. |
| type | Yes | [IPTransitConfigType](/api-reference/ipt/datastructure.md#iptransitconfigtype) | Configuration change operation type. |
| bandwidth | No | Integer | Target bandwidth (Mbps).
Required when type is BANDWIDTH.
|
| commitBandwidth | No | Integer | Committed bandwidth (Mbps).
Effective when type is BANDWIDTH. If not specified, defaults to the same value as bandwidth.
|
| bfd | No | [BFDConfig](/api-reference/ipt/datastructure.md#bfdconfig) | BFD configuration.
Required when type is BFD. Pass null to disable BFD.
|
| bgp | No | [BgpConfigParam](/api-reference/ipt/datastructure.md#bgpconfigparam) | BGP configuration parameters.
Fill in the corresponding sub-fields when type is BGP\_ROUTE\_TYPE, BGP\_ASN\_AS\_SET, or BGP\_PASSWORD.
|
| publicIPv4BlockSize | No | Integer | IPv4 CIDR netmask length (24-32).
Required when type is ADD\_CIDR\_BLOCK, EXPAND\_CIDR\_BLOCK, or SHRINK\_CIDR\_BLOCK.
|
| ipUuid | No | String | UUID of the target IP block.
Required when type is DEL\_CIDR\_BLOCK, EXPAND\_CIDR\_BLOCK, or SHRINK\_CIDR\_BLOCK.
|
| ipNetworkType | No | [IPTransitIpNetworkType](/api-reference/ipt/datastructure.md#iptransitipnetworktype) | IP network type.
Effective when type is ADD\_CIDR\_BLOCK. Default: BGP\_IP.
|
| marketingInfo | No | [MarketingInfo](/api-reference/ipt/datastructure.md#marketinginfo) | Marketing activity information, including whether to use a POC voucher.
Valid only when type is ADD\_CIDR\_BLOCK. If no POC voucher is available in the system, the order for adding the IP block will fail.
|
## 3. Output Parameters
| Parameter Name | Type | Description |
| -------------- | ------ | --------------------------------------------------------------------------------------------------------------------- |
| requestId | String | The unique request ID, which is returned for each request.
RequestId is required for locating a problem.
|
## 4. Code Example
{% tabs %}
{% tab title="Example" %}
**1. Modify the bandwidth of an IP Transit to 200 Mbps, with a committed bandwidth of 100 Mbps.**
```json
POST /api/v2/ipt HTTP/1.1
Host: console.zenlayer.com
Content-Type: application/json
X-ZC-Action: ModifyIPTransitConfig
Request:
{
"iptId": "your-ipt-id",
"type": "BANDWIDTH",
"bandwidth": 200,
"commitBandwidth": 100
}
Response:
{
"requestId": "T12345678-ABCD-1234-EFGH-000000000004",
"response": {
"requestId": "T12345678-ABCD-1234-EFGH-000000000004"
}
}
```
**2. Modify the BGP inbound route type to receive only default routes.**
```json
POST /api/v2/ipt HTTP/1.1
Host: console.zenlayer.com
Content-Type: application/json
X-ZC-Action: ModifyIPTransitConfig
Request:
{
"iptId": "your-ipt-id",
"type": "BGP_ROUTE_TYPE",
"bgp": {
"routeType": "DEFAULT_ROUTES"
}
}
Response:
{
"requestId": "T12345678-ABCD-1234-EFGH-000000000005",
"response": {
"requestId": "T12345678-ABCD-1234-EFGH-000000000005"
}
}
```
**3. Add a /28 public IPv4 CIDR block.**
```json
POST /api/v2/ipt HTTP/1.1
Host: console.zenlayer.com
Content-Type: application/json
X-ZC-Action: ModifyIPTransitConfig
Request:
{
"iptId": "your-ipt-id",
"type": "ADD_CIDR_BLOCK",
"publicIPv4BlockSize": 28,
"marketingInfo": {
"usePocVoucher": true
}
}
Response:
{
"requestId": "T12345678-ABCD-1234-EFGH-000000000006",
"response": {
"requestId": "T12345678-ABCD-1234-EFGH-000000000006"
}
}
```
**4. Disable BFD detection.**
```json
POST /api/v2/ipt HTTP/1.1
Host: console.zenlayer.com
Content-Type: application/json
X-ZC-Action: ModifyIPTransitConfig
Request:
{
"iptId": "your-ipt-id",
"type": "BFD",
"bfd": null
}
Response:
{
"requestId": "T12345678-ABCD-1234-EFGH-000000000007",
"response": {
"requestId": "T12345678-ABCD-1234-EFGH-000000000007"
}
}
```
{% 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 |
| ---------------- | --------------------------------------------- | ---------------------------------------------------------------------------------------------------------- |
| 404 | INVALID\_RIPT\_NOT\_FOUND | The IP Transit instance does not exist. |
| 409 | INVALID\_RIPT\_HA\_ROLE | The IP Transit's HA role does not apply to this operation. |
| 400 | INVALID\_RIPT\_STATE | The IP Transit state does not support this operation. |
| 400 | INVALID\_RIPT\_IP\_INVALID\_RANGE | Invalid IP mask range. |
| 400 | INVALID\_RIPT\_BANDWIDTH\_LESS\_THAN\_COMMIT | `bandwidth` must be greater than or equal to `commitBandwidth` when internetType is ByInstanceBandwidth95. |
| 403 | OPERATION\_DENIED\_LAST\_CIDR | The last CIDR block cannot be deleted. |
| 409 | INVALID\_RIPT\_INTERCONNECT\_BLOCK\_IMMUTABLE | The IP Transit interconnect address block cannot be modified after creation. |
| 403 | OPERATION\_DENIED\_CIDR\_STATUS | The CIDR block state does not support this operation. |
| 403 | OPERATION\_DENIED\_INVALID\_CIDR\_SIZE | Invalid CIDR block size. |
| 403 | OPERATION\_DENIED\_IP\_IN\_USE | Some IP addresses are still in use. |
| 409 | INVALID\_RIPT\_HA\_MODE\_NOT\_ACTIVE\_STANDBY | Primary/secondary switchover is only allowed in active/standby mode. |
| 404 | INVALID\_RIPT\_HA\_CHILD\_NOT\_FOUND | The sub-IP Transit does not belong to this HA parent instance. |
| 409 | INVALID\_RIPT\_HA\_STATUS\_NOT\_RUNNING | The IP Transit state must be RUNNING to perform HA operations. |
| 403 | OPERATION\_DENIED\_HA\_BFD\_DISABLE | BFD cannot be disabled for an HA IP Transit. |
| 400 | INVALID\_RIPT\_ROUTING\_TYPE\_NOT\_BGP | Modifying BGP configuration is not supported because the routing type of the IP Transit is not BGP. |
| 403 | OPERATION\_DENIED\_STANDARD\_BGP\_ADD\_CIDR | IP Transits with the Standard BGP tier do not support adding public IP blocks. |
| 400 | INVALID\_RIPT\_BGP\_ASN\_LIST\_MISSING | At least one of `bgp.asnList` and `bgp.asSetList` must be specified. |