This topic describes how to allocate an IPv6 CIDR block to a VSwitch.


  1. Log on to the VPC console.
  2. In the left-side navigation pane, click VSwitches.
  3. Select the region where your VSwitch resides.
    Note The following regions support IPv6 gateways: China (Beijing), China (Zhangjiakou), China (Hohhot), China (Hangzhou), China (Shanghai), China (Shenzhen), China (Chengdu), China (Hong Kong), Singapore (Singapore), and US (Virginia).
  4. On the VSwitches page, find the target VSwitch, and click Enable IPv6 CIDR Block in the IPv6 CIDR Block column.
  5. Optional:In the Enable IPv6 CIDR Block dialog box, click OK.
    Note This operation is required only when IPv6 is not enabled for the VPC to which the VSwitch belongs.
  6. Specify an IPv6 CIDR block and click OK.

    The default subnet mask for the IPv6 CIDR block of a VSwitch is /64. You can enter a decimal number ranging from 0 to 255 to define the last 8 bits of the IPv6 CIDR block.

    For example, if the IPv6 CIDR block of the VPC that contains the VSwitch is 2xx1:db8::/64, you can enter 255 (FF in hexadecimal notation) in this field to define the IPv6 CIDR block of the VSwitch as 2xx1:db8::ff/64.