## Replace Hostname Associations

`client.certificateAuthorities.hostnameAssociations.update(HostnameAssociationUpdateParamsparams, RequestOptionsoptions?): HostnameAssociationUpdateResponse`

**put** `/zones/{zone_id}/certificate_authorities/hostname_associations`

Replace Hostname Associations

### Parameters

- `params: HostnameAssociationUpdateParams`

  - `zone_id: string`

    Path param: Identifier.

  - `hostnames?: Array<HostnameAssociation>`

    Body param

  - `mtls_certificate_id?: string`

    Body param: The UUID for a certificate that was uploaded to the mTLS Certificate Management endpoint. If no mtls_certificate_id is given, the hostnames will be associated to your active Cloudflare Managed CA.

### Returns

- `HostnameAssociationUpdateResponse`

  - `hostnames?: Array<HostnameAssociation>`

### Example

```node
import Cloudflare from 'cloudflare';

const client = new Cloudflare({
  apiToken: process.env['CLOUDFLARE_API_TOKEN'], // This is the default and can be omitted
});

const hostnameAssociation = await client.certificateAuthorities.hostnameAssociations.update({
  zone_id: '023e105f4ecef8ad9ca31a8372d0c353',
});

console.log(hostnameAssociation.hostnames);
```

#### Response

```json
{
  "errors": [
    {
      "code": 1000,
      "message": "message",
      "documentation_url": "documentation_url",
      "source": {
        "pointer": "pointer"
      }
    }
  ],
  "messages": [
    {
      "code": 1000,
      "message": "message",
      "documentation_url": "documentation_url",
      "source": {
        "pointer": "pointer"
      }
    }
  ],
  "success": true,
  "result": {
    "hostnames": [
      "api.example.com"
    ]
  }
}
```