ipv6_cidr_block_mask can't be optional when enabling IPv6 for vSwitch

[awx-fuyuanchu]

Hi there,

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Terraform Version

Run terraform -v to show the version. If you are not running the latest version of Terraform, please upgrade because your issue may have already been fixed.

> terraform -v
Terraform v1.0.8
on darwin_amd64

Affected Resource(s)

Please list the resources as a list, for example:

• alicloud_vswitch

If this issue appears to affect multiple resources, it may be an issue with Terraform's core, so please mention this.

Terraform Configuration Files

  # alicloud_vswitch.alicloud_vswitches["ipv6-test-1"] will be updated in-place
  ~ resource "alicloud_vswitch" "alicloud_vswitches" {
      ~ enable_ipv6       = false -> true
        id                = "vsw-xxxxxxx"
        name              = "ipv6-test-1"
        # (8 unchanged attributes hidden)
    }

Panic Output

│ Error: [ERROR] terraform-provider-alicloud/alicloud/resource_alicloud_vswitch.go:266: Resource vsw-xxxxxxx ModifyVSwitchAttribute Failed!!! [SDK alibaba-cloud-sdk-go ERROR]:
│ SDKError:
│    StatusCode: 400
│    Code: MissingParam.Ipv6CidrBlock
│    Message: code: 400, The parameter The parameter Ipv6CidrBlock is mandatory. is mandatory. request id: 3BA4E41A-97A2-5925-B454-34FCE6AF7ABB
│    Data: {"Code":"MissingParam.Ipv6CidrBlock","HostId":"xxxxxxx.aliyuncs.com","Message":"The parameter The parameter Ipv6CidrBlock is mandatory. is mandatory.","Recommend":"https://api.aliyun.com/troubleshoot?q=MissingParam.Ipv6CidrBlock&product=Vpc&requestId=3BA4E41A-97A2-5925-B454-34FCE6AF7ABB","RequestId":"3BA4E41A-97A2-5925-B454-34FCE6AF7ABB"}
│
│
│   with alicloud_vswitch.alicloud_vswitches["ipv6-test-1"],
│   on main.tf line 38, in resource "alicloud_vswitch" "alicloud_vswitches":
│   38: resource "alicloud_vswitch" "alicloud_vswitches" {
│

Expected Behavior

What should have happened?

As mentioned in this doc, ipv6_cidr_block_mask is optional. So the vSwitch will enable the IPv6 with a generated ipv6_cidr_block_mask when enable_ipv6 is set to true.

Actual Behavior

What actually happened?

Error is shown above. Missing Ipv6CidrBlock when enabling IPv6

Steps to Reproduce

Please list the steps required to reproduce the issue, for example:

1. terraform apply

Important Factoids

It'll work if I set the attribute ipv6_cidr_block_mask of the resource alicloud_vswitch.