Configure endpoint groups for intelligent routing listeners - Global Accelerator

Each listener is associated with an endpoint group. You can associate a listener with an endpoint group by specifying the region to which you want to distribute network traffic. After you associate a listener with an endpoint group, the system distributes network traffic to an endpoint in the endpoint group based on the routing type of the listener. This topic describes how to create and manage the endpoint groups of intelligent routing listeners.

Background information

After you create an intelligent routing listener for a Global Accelerator (GA) instance, the GA instance automatically selects a nearby and healthy endpoint group and forwards client requests to the optimal endpoint in the endpoint group.

Intelligent routing listeners support the following types of endpoint groups:

Default endpoint group: the endpoint group that you configured when you create a listener.
- By default, you can create two default endpoint groups for a TCP or UDP listener. If you want to create additional endpoint groups, go to the Quota Management page and increase the quota named gaplus_quota_epgs_per_listener. For more information, see Manage GA quotas.
  A default endpoint group can be deployed in only one region. You can specify a traffic distribution ratio for each endpoint group. The traffic distribution ratio specifies the proportion of traffic that is distributed to an endpoint group. For more information about how to specify traffic distribution ratios, see Distribute traffic across endpoint groups in different scenarios.
- You can create one default endpoint group for each HTTP or HTTPS listener.

Virtual endpoint group: After you create a listener, you can create a virtual endpoint group on the Endpoint Groups page.
- By default, you can create up to 10 virtual endpoint groups for each TCP, HTTP, or HTTPS listener. If you want to create additional virtual endpoint groups, go to the Quota Management page and increase the quota named gaplus_quota_vepg_per_listener. For more information, see Manage GA quotas.
- You cannot create virtual endpoint groups for UDP listeners.
After you create a virtual endpoint group for a listener, you can create a custom forwarding rule and associate the rule with the virtual endpoint group. After you associate a forwarding rule with an endpoint group, the listener forwards the requests that meet the forwarding conditions to the default endpoint group or the virtual endpoint group specified in the forwarding rule. This way, Global Accelerator (GA) can access multiple endpoints at the same time. For more information about how to create a forwarding rule, see Add and manage forwarding rules.

Note

If the TCP listener of your standard GA instance does not support virtual endpoint groups or forwarding rules, the instance may be of an earlier version. Contact your account manager to upgrade your GA instance.

Prerequisites

A standard Global Accelerator instance is created. For more information, see Create and manage standard GA instances.
A basic bandwidth plan is purchased and associated with the GA instance whose bandwidth billing method is subscription.
An application that serves as the endpoint of the standard GA instance is deployed to receive requests that are forwarded from GA. For more information about the endpoint types that are supported by GA, see the "Endpoints" section of the Overview topic.

Create a default endpoint group

Log on to the GA console.
On the Instances page, find the GA instance that you want to manage and click Configure Listeners in the Actions column.
On the Listeners tab, click Add Listener.
Note
If this is the first time that you add a listener or if no listener is created for the specified Global Accelerator instance, skip this step.
In the Configure Listener & Protocol step, select Intelligent Routing as the routing type, configure the listener protocol and port, and then click Next.
For more information, see Add and manage intelligent routing listeners.

In the Configure Endpoint Group step, configure the parameters. The following table describes the parameters.

Parameter	Description
Endpoint Group Name	Enter a name for the endpoint group.
Region	Select the region where you want to deploy the endpoint group. Note If the region where the endpoint is deployed is not supported by GA, select the region that is nearest to your endpoint. Global Accelerator forwards requests to the optimal endpoint in the endpoint group.
Configuration	Endpoints are the destinations of client requests. To add an endpoint, set the following parameters: Backend Service Type: If your backend server is deployed on Alibaba Cloud, you can select Alibaba Cloud Public IP Address, ECS, ENI, CLB, ALB, NLB, or OSS. If your backend server is not deployed on Alibaba Cloud, you can select Custom IP Address or Custom Domain Name. Note If your standard GA instance does not support ALB instances, ECS instances in VPCs, CLB instances in VPCs, NLB instances, or ENIs as endpoints, your instance may be of an earlier version. Contact your account manager to upgrade your GA instance. UDP listeners do not support ALB instances as endpoints. To ensure that your GA instance is connected to an endpoint, you must configure an access control policy for the endpoint based on the connection type. Internet connection: The access control policies of the endpoint, such as security group rules or firewall settings, must allow the public IP address of the endpoint. Private connection: The access policies of the endpoint, such as security group rules or firewall settings, must allow the CIDR block of the vSwitch to which the endpoint belongs. The number of idle private IP addresses of the vSwitch must be equal to or greater than eight. The public IP addresses of endpoints associated with a GA instance are unique and are not shared with other GA instances. For information about how to view the public IP address of an endpoint, see View the public IP address of an endpoint. If no service-linked roles exist when you specify Elastic Compute Service (ECS) instances, elastic network interfaces (ENIs), Classic Load Balancer (CLB) instances, Application Load Balancer (ALB) instances, Network Load Balancer (NLB) instances, or Object Storage Service (OSS) buckets as endpoints, the system automatically creates the corresponding service-linked role. For more information, see AliyunServiceRoleForGaVpcEndpoint, AliyunServiceRoleForGaAlb, AliyunServiceRoleForGaOss, and AliyunServiceRoleForGaNlb. Backend Services: Enter the IP address, domain name, or instance ID of the backend server. Weight: Specify a weight for the endpoint. Valid values: 0 to 255. GA distributes network traffic to endpoints based on the weights. Warning If you set the weight of an endpoint to 0, Global Accelerator stops distributing network traffic to the endpoint. Proceed with caution. You can click + Add Node to add more endpoints. You can create up to four endpoints in each endpoint group. If you want to add more endpoints, go to the Quota Management page and increase the quota. For more information, see Manage GA quotas.
Preserve Client IP	Specify whether to preserve client IP addresses. If you enable this feature, the backend server can obtain client IP addresses. For more information, see Preserve client IP addresses.
Backend Service Protocol	Select the protocol that is used by the backend service. The Backend Service Protocol parameter is available only when you configure an endpoint group for an HTTP or HTTPS listener. HTTP(default) HTTPS Note If the listener protocol is HTTP, this parameter is automatically set to HTTP and cannot be modified. If you select HTTPS for Backend Service Protocol, the backend service supports the following TLS versions: TLS 1.0, TLS 1.1, TLS 1.2, and TLS 1.3. In addition, GA automatically negotiates with the backend service on which TLS version to use. By default, TLS 1.3 is disabled. To use TLS 1.3, contact your account manager.
Protocol Version	Select the protocol version used by the backend service. The IP Version parameter is available only when you select HTTPS for Backend Service Protocol. HTTP/1.1 (default) HTTP/2 After you enable HTTP/2, backend HTTPS services can benefit from the advantages of HTTP/2 to greatly improve service performance, reduce network latency and overheads, and improve access experience. This protocol version is suitable for backend services that support HTTP/2. If your backend services support only HTTP/2, you must select HTTP/2. Note By default, the IP Version parameter is disabled. To enable this parameter, contact your account manager. If you select HTTP/2, the following limits apply: WebSocket is not supported. HTTP/2 Server Push is not supported. Google Remote Procedure Call (gRPC) requests that use HTTP/2 cannot be accelerated.
Port Mapping	If the listener port and the port that is used by the endpoint to provide services are different, you must configure this parameter. Listener Port: The specified port must fall within the port range of the listener. Endpoint Port: Enter the port over which the endpoint provides services. Valid values: 1 to 65535. If the listener port and the port that the endpoint uses to provide services are the same, you do not need to add a port mapping. GA automatically distributes client requests to the listener port of the endpoint. For TCP and UDP listeners, you can click Add Port Mapping to add multiple port mappings. The listener ports in the port mappings must be unique. For HTTP and HTTPS listeners, you can add only one port mapping. Note If the TCP or UDP listener of your standard GA instance does not allow you to configure Port Mapping, the instance may be using an earlier version. Contact your account manager to upgrade your GA instance. For TCP listeners: You cannot configure a port mapping for a virtual endpoint group. If a virtual endpoint group already exists on the listener, you cannot configure port mappings for the default endpoint group. If port mappings are configured for the default endpoint group, you cannot add a virtual endpoint group. After you configure port mappings, take note of the following limits: Port protocol: You can only change between HTTP and HTTPS. You cannot change between other protocols. Listener port: When you modify the listener port range, make sure that the new port range includes the ports configured in port mappings. For example, if you set the listener port range to 80 to 82 and map the listener ports to endpoint ports 100 to 102, the new port range must includes ports 80 to 82. You can change the port range to 80 to 90, but you cannot change the listener port range to 80 to 81. For more information, see Use GA port mappings to improve application flexibility and security.
Traffic Distribution Ratio	Set the traffic distribution ratio for the endpoint group. The Traffic Distribution Ratio parameter is available only when you configure an endpoint group for a TCP or UDP listener. Valid values: 0 to 100. Note For information about how to specify traffic distribution ratios, see Distribute traffic across endpoint groups in different scenarios. A value of 0 specifies that no traffic is forwarded to the endpoint group. A value of 100 specifies that all traffic is forwarded to the endpoint group.
Health Check	Specify whether to enable the health check feature. After you enable the feature, you can use health checks to check the status of endpoints. For more information about the health check feature, see Enable and manage health checks. Note If your GA instance uses UDP listeners, you can enable the health check feature for an endpoint only if the endpoint is associated with a TCP, HTTP, or HTTPS service. Otherwise, the endpoint is marked as unhealthy.
Health Check Protocol	Select the protocol that you want to use for health checks. Valid values: TCP, HTTP, and HTTPS. A TCP health check probes whether a server port is healthy at the network layer by sending SYN packets to the port. An HTTP health check probes whether an endpoint is healthy by simulating HTTP GET requests sent from a browser.
Port	Specify the port of the endpoint to which probe packets are sent for health checks. Valid values: 1 to 65535.
Health Check Interval	Specify the interval between two consecutive health checks. Unit: seconds. Valid values: 1 to 50. Default value: 2.
URI	Specify the URI for health checks. By default, GA sends a GET request to the default homepage of the backend service. If you do not want to use the default homepage for health checks, you can manually specify a URI. Note This parameter is supported only for HTTP and HTTPS health checks.
Healthy Threshold	The number of consecutive health check failures that must occur before a healthy endpoint is considered unhealthy, or the number of consecutive health check successes that must occur before an unhealthy endpoint is considered healthy. Valid values: 2 to 10. Default value: 3.
Tag	Specify a tag for the endpoint group. You must configure the Tag Key and Tag Value parameters. For more information, see Manage tags.

Optional. Click + Add Endpoint Group to add multiple endpoint groups and repeat the operation in Step 5 to configure the endpoint groups.
Note
You can add multiple endpoint groups only for TCP and UDP listeners.
In the Cross-border Acceleration Settings section, read Compliance Commitments Regarding Cross-border Data Transfers and select Agree to the Preceding Compliance Agreement.
This parameter is required only when cross-border acceleration is disabled for your GA instance but your service requires cross-border acceleration between the Chinese mainland and regions outside the Chinese mainland or between different countries and regions.
Click Next Step.
In the Confirm step, check the configurations and click Submit.
If you want to modify a specific setting, click Modify that corresponds to the setting. Then, you are redirected to the configuration page.

Create a virtual endpoint group

Before you can create a virtual endpoint group, you must add the default endpoint group.

Log on to the GA console.
On the Instances page, find the GA instance that you want to manage and click Configure Listeners in the Actions column.
On the Listeners tab, find the listener that you want to manage and click the number in the Virtual Endpoint Group column.
On the Endpoint Group tab, click Add Virtual Endpoint Group in the Virtual Endpoint Group section.
On the Add Virtual Endpoint Group page, set the parameters and click Created.
For more information, see Create a default endpoint group.

What to do next

Operation	Description
Modify an endpoint group	On the Listeners tab, find the listener that you want to modify and click the endpoint group ID in the Default Endpoint Group column. On the Endpoint Group tab, find the default endpoint group or virtual endpoint group that you want to modify and click Modify in the Actions column. On the Modify Endpoint Group or Edit Virtual Endpoint Group page, modify the name and endpoints of the endpoint group, and then click Save. For more information about how to configure a default endpoint group, see Create a default endpoint group.
Specify a traffic distribution ratio for an endpoint group	Specify a traffic distribution ratio for an endpoint group Note You can configure the Traffic Distribution Ratio parameter only when you create an endpoint group for a TCP or UDP listener. For more information about how to specify traffic distribution ratios, see Distribute traffic across endpoint groups in different scenarios. On the Listeners tab, find the listener and click Edit Endpoint Group in the Actions column. In the Configure Listener & Protocol step, click Next. In the Configure Endpoint Group step, find the endpoint group that you want to manage, specify the traffic distribution ratio, and then click Next. Valid values of the traffic distribution ratio: 0 to 100. Unit: percent. In the Confirm step, check the configurations and click Submit.
Specify the weight of an endpoint	You can specify the weight of an endpoint. The weight specifies the proportion of traffic that GA distributes to an endpoint in the endpoint group. GA calculates the sum of all endpoint weights in an endpoint group. Then, traffic is routed to endpoints based on the proportions of the weights of the endpoints. For example, if you want to distribute one third of the network traffic to Endpoint 1 and two thirds of the network traffic to Endpoint 2, you can set the weight of Endpoint 1 to 1 and the weight of Endpoint 2 to 2. To stop GA from distributing network traffic to an endpoint, set the weight of the endpoint to 0. On the Listeners tab, find the listener that you want to manage and click the endpoint group ID or number in the Default Endpoint Group or Virtual Endpoint Group column. On the Endpoint Group tab, find the endpoint group that contains the endpoint for which you want to specify the weight and click Modify in the Actions column. In the Configuration section of the Modify Endpoint Group or Edit Virtual Endpoint Group page, find the endpoint that you want to modify, specify a weight in the Weight (Valid values: 0 to 255) column, and then click Save. Valid values of the weight: 0 to 255.
View the public IP address of an endpoint	On the Listeners tab, find the listener that you want to manage and choose > View Endpoint Group in the Actions column. On the Endpoint Group tab, find the endpoint group that you want to view. The public IP addresses of endpoints in the region where the endpoint group resides are displayed in the Endpoint Group IPs column. Note The system assigns at least four public IP addresses to each endpoint. The number of public IP addresses assigned to an endpoint varies based on the following factors when different billing methods are used: The volume of traffic if the pay-as-you-go billing method is used. The CIDR blocks or the IP addresses of the endpoint are added or removed based on traffic fluctuation. You can call API operations to query the public CIDR blocks or IP addresses of an endpoint. For more information, see ListEndpointGroups and ListEndpointGroupIpAddressCidrBlocks. The instance specifications if the subscription billing method is used. When you modify the specifications of a GA instance, the public IP addresses of the endpoint may be added or removed. The added public IP addresses enters the Available state only after you manually confirm the modified specifications of the GA instance. You can confirm the modified specifications of the GA instance in the GA console or by calling the UpdateAcceleratorConfirm operation.
Delete an endpoint group	You can delete an endpoint group that you no longer require. After you delete an endpoint group, GA stops forwarding requests to the endpoint group. Warning If a listener is associated with only one endpoint group and you delete the endpoint group, the listener becomes unavailable. Proceed with caution. On the Listeners tab, find the listener that you want to modify and click the endpoint group ID in the Default Endpoint Group column. On the Endpoint Group tab, find the default endpoint group or virtual endpoint group that you want to delete and click Delete in the Actions column. In the message that appears, click OK.
Delete an endpoint	You can delete an endpoint that you no longer require. After you delete an endpoint, GA stops forwarding requests to the endpoint. If an endpoint group contains only one endpoint, you cannot delete the endpoint. On the Listeners tab, find the listener that you want to modify and click the endpoint group ID in the Default Endpoint Group column. On the Endpoint Group tab, find the default endpoint group or virtual endpoint group to which the endpoint that you want to delete belongs and click Modify in the Actions column. In the Modify Endpoint Group section of the Endpoint page, find the endpoint that you want to delete, click Actions in the Delete column, and then click Save.

References

Distribute traffic across endpoint groups in different scenarios
Examples of how to configure traffic distribution ratios for multiple endpoint groups
Configure HTTP/2 origin fetch for a GA instance
CreateEndpointGroup: creates an endpoint group for a standard GA instance.
CreateEndpointGroups: creates multiple endpoint groups for a standard GA instance.
UpdateEndpointGroup: modifies an endpoint group of a standard GA instance.
DeleteEndpointGroup: deletes an endpoint group of a standard GA instance.