Updated on 2024-10-25 GMT+08:00

Creating a VPC and Subnet

Scenarios

Virtual Private Cloud (VPC) allows you to provision logically isolated virtual private networks for cloud resources, such as cloud servers, containers, and databases.

You can create a VPC, specify a CIDR block, and create one or more subnets for the VPC. A VPC comes with a default route table that enables subnets in the VPC to communicate with each other.

Procedure

  1. Go to the Create VPC page.
  2. On the Create VPC page, set parameters for the VPC and subnets as prompted.
    Figure 1 Creating a VPC and subnet
    Table 1 VPC parameter descriptions

    Parameter

    Description

    Example Value

    Region

    The region where the VPC belongs. Select the region nearest to you to ensure the lowest latency possible.

    EU-Dublin

    Name

    The VPC name. The name:
    • Can contain 1 to 64 characters.
    • Can contain letters, digits, underscores (_), hyphens (-), and periods (.).

    vpc-test

    IPv4 CIDR Block

    The CIDR block of the VPC. The CIDR block of a subnet can be the same as the CIDR block for the VPC (for a single subnet in the VPC) or a subset of the CIDR block for the VPC (for multiple subnets in the VPC).

    The following CIDR blocks are supported:
    • 10.0.0.0/8-24
    • 172.16.0.0/12-24
    • 192.168.0.0/16-24

    This parameter will be CIDR Block in regions where IPv4/IPv6 dual stack is not supported, and IPv4 CIDR Block if IPv4/IPv6 dual stack is supported.

    10.0.0.0/8

    Enterprise Project

    The enterprise project to which the VPC belongs.

    An enterprise project facilitates project-level management and grouping of cloud resources and users. The name of the default project is default.

    For details about creating and managing enterprise projects, see the Enterprise Management User Guide.

    default

    Advanced Settings (Optional) > Tag

    The VPC tag. Click to expand the configuration area and set this parameter.

    Add tags to help you quickly identify, classify, and search for your VPCs.

    For details, see Managing VPC Tags.

    • Key: vpc_key1
    • Value: vpc-01

    Advanced Settings (Optional) > Description

    Supplementary information about the VPC. Click to expand the configuration area and set this parameter.

    Enter the description about the VPC in the text box as required.

    The VPC description can contain a maximum of 255 characters and cannot contain angle brackets (< or >).

    N/A

    Table 2 Subnet parameter descriptions

    Parameter

    Description

    Example Value

    Name

    The subnet name. The name:
    • Can contain 1 to 64 characters.
    • Can contain letters, digits, underscores (_), hyphens (-), and periods (.).

    subnet-01

    AZ

    An AZ is a geographic location with independent power supply and network facilities in a region. AZs are physically isolated, and AZs in the same VPC are interconnected through an internal network.

    Each region contains multiple AZs. If one AZ is unavailable, other AZs in the same region continue to provide services.

    • By default, all instances in different subnets of the same VPC can communicate with each other and the subnets can be in different AZs. For example, if you have a VPC with two subnets, A01 in AZ 1 and A02 in AZ 2. Subnet A01 and A02 can communicate with each other by default.
    • A cloud resource and its subnet can be in different AZs. For example, a cloud server in AZ 1 can use a subnet in AZ 3. If AZ 3 becomes faulty, cloud servers in AZ 1 can still use the subnet in AZ 3, and your services are not interrupted.

    For details, see Region and AZ.

    AZ1

    IPv4 CIDR Block

    The IPv4 CIDR block of the subnet. This parameter is displayed only in regions where IPv4/IPv6 dual stack is supported.

    A subnet is a unique CIDR block with a range of IP addresses in a VPC. Comply with the following principles when planning subnets:

    • Planning CIDR block size: After a subnet is created, the CIDR block cannot be changed. You need to properly plan the CIDR block in advance based on the number of IP addresses required by your service.
      • The subnet CIDR block size cannot be too small. Ensure that the number of available IP addresses in the subnet meets service requirements. Remember that the first and last three addresses in a subnet CIDR block are reserved for system use. For example, in subnet 10.0.0.0/24, 10.0.0.1 is the gateway address, 10.0.0.253 is the system interface address, 10.0.0.254 is used by DHCP, and 10.0.0.255 is the broadcast address.
      • The subnet CIDR block cannot be too large, either. If you use a CIDR block that is too large, you may not have enough CIDR blocks available for new subnets, which can be a problem when you want to scale out services.
    • Avoiding subnet CIDR block conflicts: Avoid CIDR block conflicts if you need to connect two VPCs or connect a VPC to an on-premises data center.

      If the subnet CIDR blocks at both ends of the network conflict, create a subnet.

    For details about subnet planning, see VPC and Subnet Planning.

    10.0.0.0/24

    IPv6 CIDR Block (Optional)

    The IPv6 CIDR block of the subnet. This parameter is displayed only in regions where IPv4/IPv6 dual stack is supported.

    After the IPv6 function is enabled, the system automatically assigns an IPv6 CIDR block to the created subnet. Currently, the IPv6 CIDR block cannot be customized. IPv6 cannot be disabled after the subnet is created.

    For details, see IPv4 and IPv6 Dual-Stack Network.

    -

    Associated Route Table

    The default route table with which the subnet will be associated. A route table contains a set of routes that are used to control the traffic routing for your subnets in a VPC. Each VPC comes with a default route table that will be automatically associated with subnets. This allows subnets in a VPC to communicate with each other.

    If the default route table cannot meet your requirements, you can create a custom route table and associate subnets with it. Then, the default route table controls inbound traffic to the subnets, while the custom route table controls outbound traffic from the subnets. For details, see Creating a Custom Route Table.

    -

    Advanced Settings (Optional) > Gateway

    The gateway address of the subnet. Click to expand the configuration area and set this parameter.

    Retain the default value unless there are special requirements.

    10.0.0.1

    Advanced Settings (Optional) > DNS Server Address

    The DNS server addresses. Click to expand the configuration area and set this parameter.

    Huawei Cloud private DNS server addresses are entered by default. This allows ECSs in a VPC to communicate with each other and also access other cloud services using private domain names without exposing their IP addresses to the Internet.

    You can change the default DNS server addresses if needed. This may interrupt your access to cloud services.

    You can also click Reset on the right to restore the DNS server addresses to the default value.

    A maximum of two DNS server IP addresses can be configured. Multiple IP addresses must be separated using commas (,).

    100.125.x.x

    Advanced Settings (Optional) > Domain Name

    The domain name. Click to expand the configuration area and set this parameter.

    Enter domain names (), separated with spaces. A maximum of 254 characters are allowed. A domain name can consist of multiple labels (max. 63 characters each).

    To access a domain name, you only need to enter the domain name prefix. ECSs in the subnet automatically match the configured domain name suffix.

    If the domain names are changed, ECSs newly added to this subnet will use the new domain names.

    If an existing ECS in this subnet needs to use the new domain names, restart the ECS or run a command to restart the DHCP Client service or network service.

    test.com

    Advanced Settings (Optional) > IPv4 DHCP Lease Time

    The period during which a client can use an IP address automatically assigned by the DHCP server. Click to expand the configuration area and set this parameter.

    The period during which a client can use an IP address automatically assigned by the DHCP server. After the lease time expires, a new IP address will be assigned to the client.
    • Limited: Set the DHCP lease time. The unit can be day or hour.
    • Unlimited: The DHCP lease time does not expire.

    After you change the DHCP lease time on the console, the change is applied automatically when the DHCP lease of an instance (such as ECS) is renewed. You can wait for the system to renew the lease or manually renew the lease. Renewing lease will not change the IP address used by the instance. If you want the new lease time to take effect immediately, manually renew the lease or restart the ECS.

    -

    Advanced Settings (Optional) > Tag

    The subnet tag. Click to expand the configuration area and set this parameter.

    Add tags to help you quickly identify, classify, and search for your subnets.

    For details, see Managing Subnet Tags.

    • Key: subnet_key1
    • Value: subnet-01

    Advanced Settings (Optional) > Description

    Supplementary information about the subnet. Click to expand the configuration area and set this parameter.

    Enter the description about the subnet in the text box as required.

    The subnet description can contain a maximum of 255 characters and cannot contain angle brackets (< or >).

    N/A

  3. Click Create Now.

    Return to the VPC list and view the new VPC.

Follow-up Operations

After the VPC and subnets are created, you need to create other cloud resources in the subnets. For details, see Setting Up an IPv4/IPv6 Dual-Stack Network In a VPC and Setting Up an IPv4/IPv6 Dual-Stack Network In a VPC.