1.  在测试环境下存在一个虚机，该虚机有一个ipv4的虚拟网卡, ip地址为192.168.1.127

2. 通过以下配置把单栈ipv4网卡变为双栈ipv4和ipv6网卡

(1) 在当前network下创建一个ipv6子网

openstack subnet create --subnet-pool  b09ec6e7-7ee5-4d2b-bb47-806cd5fdbcb1  --ip-version 6 --network e6861a5d-fba4-4fdd-bd8b-7b7708adffd1  subnet-ipv6

(2)  把新建的ipv6子网加入当前vpc的router下,例如：

openstack router add subnet test-router1 1426bc9a-fb69-4241-82b8-84e7eb82efe8

(3) 查询该虚机的虚拟网卡id

openstack port list --device-id 3adc5a86-56d3-455e-b059-0103a881f3d5
返回：
+--------------------------------------+------+-------------------+---------------------------------------------------------------------------------------+--------+
| ID                                   | Name | MAC Address       | Fixed IP Addresses                                                                    | Status |
+--------------------------------------+------+-------------------+---------------------------------------------------------------------------------------+--------+
| 832082eb-443a-49f4-8c04-1bda6a9579c8 |      | fa:16:3e:2d:b8:c0 | ip_address='192.168.1.127', subnet_id='be91506e-e745-4fd1-ad29-d88acee26a2f'          | ACTIVE |
|                                      |      |                   | ip_address='fc00:100:127:1225::3e9', subnet_id='1426bc9a-fb69-4241-82b8-84e7eb82efe8' |        |
+--------------------------------------+------+-------------------+---------------------------------------------------------------------------------------+--------+

(4) 使用新创建ipv6子网来更新该虚机网卡

openstack port set --fixed-ip subnet=1426bc9a-fb69-4241-82b8-84e7eb82efe8   832082eb-443a-49f4-8c04-1bda6a9579c8

(5) 重启该虚机，使虚机重新获取ipv4/ipv6地址

(6) 测试该虚机ipv4和ipv6流量