Updated on 2024-07-02 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.

    CN-Hong Kong

    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 IPv4 CIDR block of the VPC. Consider the following when specifying a CIDR block:
    • Number of IP addresses: Reserve sufficient IP addresses for subsequent business growth.
    • IP address ranges: Avoid IP address conflicts if you need to connect a VPC to an on-premises data center or connect two VPCs.
    When you create a VPC, we recommend that you use the private IPv4 address ranges specified in RFC 1918 as the CIDR block:
    • 10.0.0.0/8-24: The IP address ranges from 10.0.0.0 to 10.255.255.255, and the mask ranges from 8 to 24.
    • 172.16.0.0/12-24: The IP address ranges from 172.16.0.0 to 172.31.255.255, and the mask ranges from 12 to 24.
    • 192.168.0.0/16-24: The IP address ranges from 192.168.0.0 to 192.168.255.255, and the mask ranges from 16 to 24.
    In addition to the preceding addresses, you can create a VPC with a publicly routable CIDR block that falls outside of the private IPv4 address ranges specified in RFC 1918. However, the following system and public reserved addresses must be excluded:
    • Reserved system CIDR blocks
      • 100.64.0.0/10
      • 214.0.0.0/7
      • 198.18.0.0/15
      • 169.254.0.0/16
    • Reserved public CIDR blocks
      • 0.0.0.0/8
      • 127.0.0.0/8
      • 240.0.0.0/4
      • 255.255.255.255/32

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

    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.

    NOTE:

    If your organization has configured tag policies for VPCs, you need to add tags to your VPCs based on the policies. If you add a tag that does not comply with the tag policies, VPCs may fail to be created. Contact your administrator to learn more about tag policies.

    • 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

    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.
    • Select Central if you want to provision cloud resources on the cloud and run your workloads on the cloud.
    • Select Edge if you want to provision cloud resources to an edge site and run workloads at the edge site. For details about edge sites, see CloudPond.

    For details, see Region and AZ.

    You can select an AZ for a subnet only in certain regions. See the available regions on the management console.

    AZ1

    Subnet Name

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

    subnet-01

    CIDR Block

    The CIDR block of the subnet. This parameter is displayed only in regions where IPv4/IPv6 dual stack is not supported.

    Set the IPv4 CIDR block of the subnet. For details, see section "IPv4 CIDR Block".

    10.0.0.0/24

    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:

    • Plan subnets as required. You can create different subnets for different modules in a VPC. For example, in VPC-A, you can create subnet A01 for web services, subnet A02 for management services, and subnet A03 for data services. You can leverage network ACLs to control access to each subnet.
    • Avoid CIDR block conflicts. When you need to connect subnets in different VPCs or connect a VPC and an on-premises data center, ensure that the CIDR blocks of the subnets at both ends do not conflict.

    A subnet mask can be between the netmask of its VPC CIDR block and /28 netmask. If a VPC CIDR block is 10.0.0.0/16, its subnet mask can between 16 to 28.

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

    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. Subnets in the VPC are then automatically associated with the default route table. The default route table ensures that subnets in a VPC can 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.

    NOTE:
    The command for updating the DHCP configuration depends on the ECS OS. The following commands are for your reference.
    • Restart the DHCP Client service: service dhcpd restart
    • Restart the network service: service network restart

    test.com

    Advanced Settings (Optional) > 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.

    For details, see How Do I Make the Changed DHCP Lease Time of a Subnet Take Effect Immediately?

    -

    Advanced Settings (Optional) > NTP Server Address

    The IP address of the NTP server. Click to expand the configuration area and set this parameter.

    If you want to add NTP server addresses for a subnet, you can specify NTP Server Address. The IP addresses are added in addition to the default NTP server addresses.

    • If you add or change the NTP server addresses of a subnet, you need to renew the DHCP lease for or restart all the ECSs in the subnet to make the change take effect immediately.
    • If the NTP server addresses have been cleared out, restarting the ECSs will not help. You must renew the DHCP lease for all ECSs to make the change take effect immediately.

    192.168.2.1

    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.

    NOTE:

    If you have configured tag policies for subnets, you need to add tags to your subnets based on the tag policies. If you add a tag that does not comply with the tag policies, subnets may fail to be created. Contact the administrator to learn more about tag policies.

    • 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.