# CreateLoadBalancer
## 1. API Description
This API (CreateLoadBalancer) is used to create a load balancing instance.
#### Prerequisites
* Query the available zones for creating load balancers: call the [DescribeLoadBalancerZones](/api-reference/compute/bmc/load-balancing/describeloadbalancerzones.md).
* Query whether the load balancing IP can be created in a zone: call the [DescribeLoadBalancerIPv4](https://github.com/zenlayer/zenlayercloud-api-doc-en/blob/main/bmc/load-balancing/describeloadbalanceripv4.md) or [DescribeLoadBalancerIPv6](https://github.com/zenlayer/zenlayercloud-api-doc-en/blob/main/bmc/load-balancing/describeinstances.md).
* Query whether the load balancing specifications can be created in a zone: call the [DescribeLoadBalancerSpecs](/api-reference/compute/bmc/load-balancing/describeloadbalancerspecs.md).
* Cost estimation: to know of load balancer pricing, see [Pricing](https://docs.console.zenlayer.com/welcome/pricing/general-pricing-rules) for more details.
{% hint style="info" %} **Note**
* If you create a subscription instance, the amount required will be pre-deducted. If the balance is insufficient, the request will fail. If you create a pay-as-you-go instance, please ensure your account balance is sufficient before calling this API.
* Vouchers can be used for fee deduction in instance creation. See [Vouchers](https://docs.console.zenlayer.com/welcome/platform/billing-center/vouchers) for more details.
{% endhint %}
## 2. Input Parameters
The following request parameter list only provides API request parameters.
| Parameter Name | Required | Type | Description |
| --------------------- | -------- | ---------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| zoneId | Yes | String | The zone ID. |
| loadBalancerName | Yes | String | The name of the load balancer. |
| chargeType | Yes | [ChargeType](/api-reference/compute/bmc/datastructure.md#chargetype) | Pricing model.
PREPAID : subscription;
POSTPAID : pay-as-you-go.
|
| bandwidth | Yes | Integer | Bandwidth value.
Value range: \[ 1,1024 ].
Unit: Mbps .
Value range: \[1, 10240]
|
| ipType | Yes | String | Specify the type of IP added to the load balancer.
Available values:
IPv4 IPv6
|
| clientToken | No | String | Used to ensure the idempotency of the request. |
| instanceChargePrepaid | No | [ChargePrepaid](/api-reference/compute/bmc/datastructure.md#chargeprepaid) | Subscription mode.
Details of the monthly or yearly subscription configurations, including the subscription period, auto-renewal, etc.
It is required if the pricing model is PREPAID .
|
| vipCount | No | Integer | Number of additional VIPs to be purchased.
The load balancer binds 1 IP of the specified type by default.
|
| subnetId | No | String | Subnet ID.
The subnet ID must be specified when creating a VIP4 type. The primary and secondary IPs of the instance will be obtained in the subnet.
|
| cidrBlockId | No | String | CIDR block ID.
The CIDR block ID needs to be specified when creating a VIP6 type. If there is only one CIDR block in the zone, it can be unspecified and the CIDR will be used by default.
|
| masterIp | No | String | Primary IP. |
| backupIp | No | String | Secondary IP. |
| marketingOptions | No | [MarketingInfo](/api-reference/compute/bmc/datastructure.md#marketinginfo) | Information on marketing campaigns. |
| tags | No | [TagAssociation](/api-reference/compute/bmc/datastructure.md#tagassociation) | Bound tags when creating resources.
Tag keys must be unique.
|
## 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.
|
| orderNumber | String | Order number. |
| loadBalancerId | String | Load balancer ID. |
## 4. Code Example
{% tabs %}
{% tab title="Example" %}
**Create a load balancing instance.**
```json
POST /api/v2/bmc HTTP/1.1
Host: console.zenlayer.com
Content-Type: application/json
X-ZC-Action: CreateLoadBalancer
Request:
{
"zoneId": "HKG-A",
"loadBalancerName": "xxxx",
"specName": "xxxx",
"clientToken": "xxxx",
"chargeType": "xxxx",
"bandwidth": 100,
"subnetId": "xxxx",
"ipType": "IPv4"
}
Response:
{
"requestId": "TEEFDCA5B-76FB-4E91-A18E-DF7F5D2CE41F",
"response": {
"requestId": "TEEFDCA5B-76FB-4E91-A18E-DF7F5D2CE41F",
"orderNumber": "xxxx",
"loadBalancerId": "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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