Help Center/ Virtual Private Network/ User Guide (Paris Regions) / Getting Started/ (Optional) Creating a Subnet for the VPC
Updated on 2022-01-25 GMT+08:00
View PDF
Share

(Optional) Creating a Subnet for the VPC

Scenarios

A VPC comes with a default subnet. If the default subnet cannot meet your requirements, you can create one.

The subnet is configured with DHCP by default. When an ECS using this VPC starts, the ECS automatically uses DHCP to obtain an IP address.

Procedure

  1. Log in to the management console.
  1. On the console homepage, under Network, click Virtual Private Cloud.
  2. In the navigation pane on the left, click Virtual Private Cloud.
  3. On the Virtual Private Cloud page, locate the VPC for which a subnet is to be created and click the VPC name.
  4. On the displayed Subnets tab, click Create Subnet.
  5. Set the parameters as prompted.

    Table 1 Parameter descriptions

    Parameter

    Description

    Example Value

    Name

    The subnet name.

    The name can contain a maximum of 64 characters, which may consist of letters, digits, underscores (_), hyphens (-), and periods (.). The name cannot contain spaces.

    Subnet

    CIDR Block

    The CIDR block for the subnet. This value must be within the VPC CIDR block.

    192.168.0.0/24

    Advanced Settings

    You can retain the default settings or customize the settings. You can click Advanced Settings to configure advanced subnet parameters.

    Default

    Gateway

    The gateway address of the subnet.

    192.168.0.1

    DNS Server Address

    By default, two DNS server addresses are configured. You can change them if necessary. Multiple IP addresses must be separated using commas (,).

    100.125.x.x
  6. Click OK.

Notes

When a subnet is created, there are five reserved IP addresses, which cannot be used. For example, in a subnet with CIDR block 192.168.0.0/24, the following IP addresses are reserved:

  • 192.168.0.0: Network ID. This address is the beginning of the private IP address range and will not be assigned to any instance.
  • 192.168.0.1: Gateway address.
  • 192.168.0.253: Reserved for the system interface. This IP address is used by the VPC for external communication.
  • 192.168.0.254: DHCP service address.
  • 192.168.0.255: Network broadcast address.

If you set Advanced Settings to Custom during subnet creation, the reserved IP addresses may be different from the default ones, but there will still be five of them. The specific addresses depend on your subnet settings.

Parent topic: Getting Started