A virtual private cloud (VPC) is a private network in the cloud. You can manage your VPC based on your business requirements. For example, you can specify CIDR blocks, and configure route tables and gateways for your VPC. You can also add secondary CIDR blocks to a VPC. This topic describes how to create and manage a VPC.

Operations

Create a VPC and a vSwitch

Make a networking plan before you create a VPC and a vSwitch. For more information, see Plan networks.

  1. Log on to the VPC console.
  2. In the top navigation bar, select the region where you want to create a VPC and a vSwitch.
    Note The VPC and the cloud resources that you want to deploy in the VPC must belong to the same region.
  3. On the VPC page, click Create VPC.
  4. On the Create VPC page, set the following parameters.
    Parameter Description
    VPC
    Region Displays the region where you want to create the VPC.
    Name Enter a name for the VPC.
    IPv4 CIDR Block Enter the primary IPv4 CIDR block of the VPC.
    • You can specify one of the following CIDR blocks or their subsets as the primary IPv4 CIDR block of the VPC: 192.168.0.0/16, 172.16.0.0/12, and 10.0.0.0/8. These CIDR blocks are standard private CIDR blocks as defined by Request for Comments (RFC) documents. The subnet mask must be 8 to 28 bits in length. For example, you can enter 192.168.0.0/24.
    • You can also use a custom CIDR block other than 100.64.0.0/10, 224.0.0.0/4, 127.0.0.0/8, 169.254.0.0/16, and their subnets as the primary IPv4 CIDR block of the VPC.
    • In scenarios where multiple VPCs are used or in hybrid cloud scenarios where data centers and VPCs are used, we recommend that you use subsets of standard RFC CIDR blocks as VPC CIDR blocks with subnet masks no more than 16 bits in length. Make sure that the CIDR blocks of the VPCs do not overlap in both scenarios. In addition, the CIDR blocks of the VPCs cannot overlap with those of the data centers in hybrid cloud scenarios.
    Note After you create a VPC, you cannot change its primary IPv4 CIDR block. However, you can add a secondary IPv4 CIDR block to the VPC. For more information, see Add a secondary CIDR block.
    IPv6 CIDR Block Specify whether to assign an IPv6 CIDR block to the VPC. In this example, Assign (Default) is selected.

    If you set this parameter to Assign, the system automatically creates an IPv6 gateway of Free Edition for this VPC, and assigns an IPv6 CIDR block with the subnet mask /56, such as 2408:4005:3c5:6e00::/56. By default, IPv6 addresses are used only for communication within private networks. If you want to use an IPv6 address to access the Internet or to be accessed by IPv6 clients over the Internet, you must purchase a public bandwidth plan. For more information, see Enable and manage IPv6 Internet bandwidth.

    Note
    • The following regions support IPv6 CIDR blocks: China (Qingdao), China (Beijing), China (Zhangjiakou), China (Hohhot), China (Ulanqab), China (Hangzhou), China (Shanghai), China (Fuzhou-Local Region), China (Shenzhen), China (Heyuan), China (Guangzhou), China (Chengdu), China (Hong Kong), Philippines (Manila), Singapore, US (Virginia), and Germany (Frankfurt).
    • After you create a VPC, you cannot change its primary IPv6 CIDR block. However, you can add a secondary IPv6 CIDR block to the VPC. For more information, see Add a secondary CIDR block.
    Description Enter a description for the VPC.
    Resource Group Select the resource group to which the VPC belongs.
    Advanced Settings
    Enable IPv4 Gateway
    • Disable: Create the VPC and a vSwitch without creating an IPv4 gateway. This is the default value.
    • Enable: After you create the VPC, the system automatically creates an IPv4 gateway.

    In this example, Enable is selected.

    Note
    • For more information about the regions that support IPv4 gateways, see Features and supported regions.
    • If you enable the IPv4 gateway feature, IPv4 gateways can be created only when the VPC has an Internet NAT gateway that is compatible with IPv4 gateways. If the Internet NAT gateway is incompatible with IPv4 gateways, you must switch the mode of the NAT gateway to enable it to support IPv4 gateways, create a new VPC, and then enable the IPv4 gateway feature for the VPC. For more information about how to switch to an Internet NAT gateway that is compatible with IPv4 gateways, see Change the mode of an Internet NAT gateway.
    vSwitch
    Name

    Enter a name for the vSwitch.

    Zone

    In the drop-down list, select a zone for the vSwitch. In the same VPC, vSwitches in different zones can communicate with each other.

    The drop-down list shows whether Elastic Compute Service (ECS) instances, ApsaraDB RDS instances, internal-facing Classic Load Balancer (CLB) instances, and internal-facing Application Load Balancer (ALB) instances are supported in each zone. The supported cloud resources vary based on the zone and the creation time of the cloud resources. The instances provided in this topic are for reference only. The actual instances on the buy page shall prevail.

    IPv4 CIDR Block
    Enter an IPv4 CIDR block for the vSwitch. When you specify a CIDR block for the vSwitch, take note of the following limits:
    • The CIDR block of a vSwitch must be a subset of the CIDR block of the VPC to which the vSwitch belongs.

      For example, if the CIDR block of a VPC is 192.168.0.0/16, the CIDR block of a vSwitch in the VPC can range from 192.168.0.0/17 to 192.168.0.0/29.

    • The first IP address and the last three IP addresses of a vSwitch CIDR block are reserved.

      For example, if a vSwitch CIDR block is 192.168.1.0/24, the IP addresses 192.168.1.0, 192.168.1.253, 192.168.1.254, and 192.168.1.255 are reserved.

    • If a vSwitch is required to communicate with vSwitches in other VPCs or with data centers, make sure that the CIDR block of the vSwitch does not overlap with the destination CIDR blocks.
    Note After you create a vSwitch, you cannot change its CIDR block.
    IPv6 CIDR Block
    Specify whether to enable IPv6 for the vSwitch. If you enable IPv6, you must specify an IPv6 CIDR block for the vSwitch.
    Note
    • If your VPC is assigned an IPv6 CIDR block, you must configure the IPv6 CIDR block of the vSwitch.
    • If your VPC is not assigned an IPv6 CIDR block, you do not need to configure the IPv6 CIDR block of the vSwitch.

    In this example, Enable is selected.

    By default, the subnet mask of the IPv6 CIDR block of a vSwitch is /64. You can enter a decimal number 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 is 2408:4005:3c5:6e00::/56, you can enter 255 (ff in hexadecimal format) for the IPv6 CIDR block of the vSwitch. In this case, the IPv6 CIDR block of the vSwitch is 2408:4005:3c5:6eff::/64.

  5. Optional:To create more vSwitches, click Add below the vSwitch section and repeat the preceding step to set the parameters.
    You can create at most 10 vSwitches in each VPC.
  6. Click OK.

View a VPC

  1. Log on to the VPC console.
  2. In the top navigation bar, select the region where the VPC is created.
  3. On the VPCs page, find the VPC that you want to view and click its ID. View a VPC
  4. You can view the information about VPC Details, vRouter Basic Information, Resources, and CIDRs.
    • Click the Advanced Features tab to view the information about advanced features.

      You can view the advanced features that are supported by the VPC. For more information, see Advanced VPC features.

    • Click the Authorize Cross Account Attach CEN tab to grant permissions to a Cloud Enterprise Network (CEN) instance of another Alibaba Cloud account. This way, you can attach the VPC to the CEN instance. For more information, see Grant permissions to an Alibaba Cloud account.
    • Click the Cross-Account VBR Authorization tab to grant permissions to a VBR that belongs to another Alibaba Cloud account. After the permissions are granted, the VPC can connect to the VBR.

Modify the basic information about a VPC

You can modify the name and description of a VPC.

  1. Log on to the VPC console.
  2. In the top navigation bar, select the region where the VPC is created.
  3. On the VPCs page, find the VPC that you want to manage and click its ID.
  4. In the VPC Details section, click Edit next to Name. In the dialog box that appears, enter a new name for the VPC and click OK.
  5. Click Edit next to Description. In the dialog box that appears, enter a new description and click OK.

Add a secondary CIDR block

Limits

  • When you create a VPC, the IPv4 CIDR block that you specified is the primary CIDR block. After the VPC is created, you cannot modify the primary IPv4 CIDR block of the VPC. However, you can add a secondary IPv4 CIDR block to the VPC. After you add a secondary IPv4 CIDR block to the VPC, both the primary and secondary IPv4 CIDR blocks are in effect.

    You can add at most five secondary IPv4 CIDR blocks to a VPC and at most three secondary IPv6 CIDR blocks to a VPC that has IPv6 enabled.

  • You can create a vSwitch with the primary IPv4 CIDR block or a secondary CIDR block of a VPC. However, the CIDR block of a vSwitch must belong to only one CIDR block of the VPC. Whether you create a vSwitch with the primary IPv4 CIDR block or a secondary CIDR block, the system automatically adds a route to a route table of the VPC. The destination CIDR block of the route is the CIDR block of the vSwitch. The CIDR block of a vSwitch cannot be the same as or larger than the destination CIDR block of a route in a route table of the VPC to which the vSwitch belongs.

    For example, 172.16.0.0/12 is added to a VPC as a secondary IPv4 CIDR block and a CEN route exists in a route table of the VPC. Overlapping routing is enabled for CEN and the destination CIDR block of the CEN route is 172.16.0.0/24. In this case, you cannot create a vSwitch with 172.16.0.0/24 or a larger CIDR block. However, you can create a vSwitch with 172.16.0.0/25 or a smaller CIDR block.

Prerequisites

Before you add a secondary IPv4 CIDR block to a VPC, make sure that a VPC is created. If you want to add a secondary IPv6 CIDR block to a VPC, you must enable IPv6 for the VPC. If you want to create a vSwitch with a secondary IPv6 CIDR block, you must enable IPv6 for the vSwitch.

  1. Log on to the VPC console.
  2. In the top navigation bar, select the region where the VPC is created.
  3. On the VPC page, find the VPC that you want to manage and click its ID.
  4. On the VPC Details page, click the CIDRs tab and perform the following operations to add a secondary CIDR block to the VPC.
    • Add a secondary IPv4 CIDR block
      1. Click the IPv4 CIDR Block tab and click Add IPv4 CIDR.
      2. In the Add Secondary CIDR dialog box, set the following parameters and click OK.
        Parameter Description
        VPC Displays the VPC to which you want to add a secondary IPv4 CIDR block.
        Secondary CIDR Select a method to configure the secondary IPv4 CIDR block:
        • Default CIDR Block: You can specify one of the following standard IPv4 CIDR blocks as the secondary IPv4 CIDR block: 192.168.0.0/16, 172.16.0.0/12, and 10.0.0.0/8.
        • Custom CIDR Block: You can also use a custom CIDR block other than 100.64.0.0/10, 224.0.0.0/4, 127.0.0.0/8, 169.254.0.0/16, or their subnets as the secondary IPv4 CIDR block of the VPC.
        When you add a secondary IPv4 CIDR block, take note of the following limits:
        • The CIDR block cannot start with 0. The subnet mask must be 8 to 28 bits in length.
        • The secondary IPv4 CIDR block cannot overlap with the primary IPv4 CIDR block or an existing secondary IPv4 CIDR block.
          For example, if the primary IPv4 CIDR block of a VPC is 192.168.0.0/16, you cannot specify one of the following CIDR blocks as the secondary IPv4 CIDR block:
          • 192.168.0.0/16.
          • A CIDR block larger than 192.168.0.0/16, for example, 192.168.0.0/8.
          • A CIDR block smaller than 192.168.0.0/16, for example, 192.168.0.0/24.
    • Add a secondary IPv6 CIDR block
      1. Click the IPv6 CIDR Block tab and click Add IPv6 CIDR Block.
      2. In the Add IPv6 CIDR Block dialog box, set the following parameters and click OK.
        Parameter Description
        IPv6 CIDR Block Type Select the type of IPv6 CIDR block. You can select only Assign (Default), which specifies a secondary IPv6 CIDR block.
        IPv6 CIDR Block Displays the secondary IPv6 CIDR block.

Delete a secondary CIDR block

You can delete a secondary CIDR block. However, you cannot delete the primary IPv4 CIDR block of a VPC.

Before you delete a secondary CIDR block, make sure that the vSwitches created within the secondary CIDR block are deleted. For more information, see Delete a vSwitch.

  1. Log on to the VPC console.
  2. In the top navigation bar, select the region where the VPC is created.
  3. On the VPCs page, find the VPC that you want to manage and click its ID.
  4. On the VPC Details page, click the CIDRs tab.
  5. On the CIDRs tab, perform the following operations to delete a secondary CIDR block:
    • Delete a secondary IPv4 CIDR block
      1. On the IPv4 CIDR Block tab, find the secondary IPv4 CIDR block that you want to delete and click Delete in the Actions column.
      2. In the message that appears, click OK.
    • Delete a secondary IPv6 CIDR block
      1. On the IPv6 CIDR Block tab, find the secondary IPv6 CIDR block that you want to delete and click Delete in the Actions column.
      2. In the message that appears, click OK.

Delete a VPC

You can delete a VPC that you no longer need. After you delete a VPC, the vRouters and route tables associated with the VPC are also deleted. Before you delete a VPC, make sure that the following requirements are met:

  • No vSwitches exist in the VPC. Otherwise, delete the vSwitches first. For more information, see Delete a vSwitch.
  • No IPv6 gateways exist in the VPC. Otherwise, delete the IPv6 gateways first. For more information, see Delete an IPv6 gateway.
  • No security groups, custom route tables, network ACLs, or DHCP options sets exist in the VPC and the VPC is not attached to a CEN instance. Otherwise, delete the resources and detach the VPC from the CEN instance.
  1. Log on to the VPC console.
  2. In the top navigation bar, select the region where the VPC is created.
  3. On the VPCs page, find the VPC that you want to delete, and click Delete in the Actions column.
  4. In the Delete VPC message, click OK.

More operations

Disable IPv6 for a VPC

If a VPC that has IPv6 enabled no longer requires IPv6, you can disable IPv6 for the VPC. Before you disable IPv6 for a VPC, you must disable IPv6 for all the vSwitches in the VPC, and delete the IPv6 gateway of the VPC.

  1. Log on to the VPC console.
  2. In the top navigation bar, select the region where the VPC is created.
  3. On the VPCs page, find the VPC for which you want to disable IPv6 and click the ID of the VPC.
  4. Click the Resources tab. In the VPC Resources section, click the number below vSwitch.
  5. On the vSwitch page, view the IPv6 CIDR blocks of vSwitches in the IPv6 CIDR Block column.
  6. Optional:If IPv6 is enabled for a vSwitch, click Disable IPv6 in the IPv6 CIDR Block column.
    You must disable IPv6 for all the vSwitches that have IPv6 enabled in the VPC.
  7. Optional:In the left-side navigation pane, choose Access to Internet > IPv6 Gateway.
  8. Optional:On the IPv6 Gateway page, check whether an IPv6 gateway exists in the VPC for which you want to disable IPv6.
    • If an IPv6 gateway exists in the VPC for which you want to disable IPv6, click Delete in the Actions column. In the message that appears, click OK.
    • If no IPv6 gateway exists in the VPC for which you want to disable IPv6, skip this step.
  9. Return to the VPCs page, find the VPC for which you want to disable IPv6, and then click Disable IPv6 in the IPv6 CIDR Block column. In the message that appears, click OK.

References