This topic describes how to create a Classic Load Balancer (CLB) instance to meet your business requirements.

Prerequisites

Before you create a CLB instance, make sure that you have have completed the required preparations. For more information, see Make preparations.

Procedure

  1. Log on to the SLB console.
  2. Choose CLB (Formerly Known as SLB) > Instances. On the Instances page, click Create CLB.
  3. Set the following parameters to configure the CLB instance.
    Parameter Description
    Region

    Select the region where you want to deploy the CLB instance.

    Note Make sure that the CLB instance and the ECS instances that act as backend servers are deployed in the same region.
    Zone Type Displays the type of zone that belongs to the specified region. A zone represents a data center that contains a set of independent infrastructure resources. The infrastructure resources (such as networks, power supply, and air-conditioning) in different zones are independent of each other. Therefore, when the infrastructure resources in one zone are down, the other zones are not affected. Each zone belongs to a specific region. A region may contain one or more zones. Multi-zone CLB instances are available in most regions.
    • Single zone: The CLB instance is deployed in only one zone.
    • Multi-zone: The CLB instance is deployed across two zones. By default, the primary zone is used to distribute network traffic. When the primary zone is down, the system automatically switches to the secondary zone and continues to provide load balancing services. This ensures high availability of the service.
    Primary Zone Select a primary zone for the CLB instance. The primary zone distributes traffic in normal conditions.
    Backup Zone Select a secondary zone for the CLB instance. By default, the secondary zone distributes traffic only when the primary zone is down.
    Instance Name Enter a name for the CLB instance.

    The name must be 1 to 80 characters in length, and can contain letters, digits, hyphens (-), forward slashes (/), periods (.),and underscores (_).

    Resource Group The resource group to which the cloud resource belongs.
    Instance Spec

    Select a specification for the CLB instance.

    The performance metrics of CLB instances vary based on the specifications. For more information, see SLB instance overview.

    Instance Type You can create an Internet-facing CLB instance or an internal-facing CLB instance based on your business requirements. The system allocates a public or private IP address to the CLB instance based on the specified instance type. For more information, see SLB instance overview.
    • Internet: If you select Internet, a public IP address is allocated to the CLB instance. You can access CLB over the Internet.
    • Intranet: If you select Intranet, a private IP address is allocated to the CLB instance. You can access the CLB service only within the networks of Alibaba Cloud. You cannot access CLB over the Internet.
    Backend Server Type Select the type of backend servers that can be attached to the CLB instance. Local region indicates that backend servers in the current region can be attached to the CLB instance.
    IP Version Select the IP protocol that is used by the CLB instance. Valid values: IPv4 and IPv6.
    Note You can create high-performance IPv6 CLB instances in the following zones:
    • China (Hangzhou): Zone E and Zone F
    • China (Beijing): Zone F and Zone G
    • China (Shanghai): Zone D and Zone E
    • China (Shenzhen): Zone D and Zone E
    • China (Zhangjiakou): Zone A and Zone B
    Quantity Specify the number of CLB instances that you want to purchase.
  4. Click Buy Now and complete the payment.