Configure endpoint groups for intelligent routing - Global Accelerator

Each listener must be associated with an endpoint group. You associate a listener with an endpoint group by specifying the region to which you want to distribute traffic. Global Accelerator then distributes traffic to the endpoints in that group based on the listener's routing type.

Background

After you configure an intelligent routing listener, the Global Accelerator (GA) instance automatically selects a nearby, healthy endpoint group to forward traffic, ensuring optimal routing for client requests.

Listeners with a smart routing type have two types of endpoint groups:

Default endpoint group: The endpoint group that you configure when you create a listener.
Virtual endpoint group: Created manually on the Endpoint Groups page after the listener is created.

The quotas and features for each endpoint group type vary based on the billing method of the GA instance:

Pay-as-you-go

Feature comparison of endpoint group types	Default endpoint group	Virtual endpoint group
Listener protocol	TCP, UDP, HTTP, or HTTPS	TCP, HTTP, or HTTPS only
Quota	Supports two default endpoint groups by default. To create more endpoint groups, increase the quota for gaplus_quota_epgs_per_listener on the Quota Management page. Each default endpoint group must be in a unique region.	Supports up to 10 virtual endpoint groups by default. To create more virtual endpoint groups, increase the quota for gaplus_quota_vepg_per_listener on the Quota Management page. TCP listeners: The region of a virtual endpoint group must be the same as the region of the default endpoint group. HTTP and HTTPS listeners: There are no regional restrictions for virtual endpoint groups.
Traffic distribution	Supported.	Supported.
Forwarding policies	Associated with the default forwarding policy by default. Also supports association with a custom forwarding policy.	Can only be associated with custom forwarding policies.

Note

If your standard GA instance does not support adding virtual endpoint groups for TCP listeners, your instance version may not support this feature. To use this feature, contact your business manager to upgrade the instance.

Subscription

Feature comparison of endpoint group types	Default endpoint group	Virtual endpoint group
Listener protocol	TCP, UDP, HTTP, or HTTPS	TCP, HTTP, or HTTPS only
Quota	TCP and UDP listeners: Supports two default endpoint groups by default. To create more endpoint groups, increase the quota for gaplus_quota_epgs_per_listener on the Quota Management page. Each default endpoint group must be in a unique region. HTTP and HTTPS listeners: Supports one default endpoint group only. Quota cannot be increased.	Supports up to 10 virtual endpoint groups by default. To create more virtual endpoint groups, increase the quota for gaplus_quota_vepg_per_listener on the Quota Management page. The region of a virtual endpoint group must be the same as the region of the default endpoint group.
Traffic distribution	TCP and UDP listeners: Supported. HTTP and HTTPS listeners: Not supported.	TCP listeners: Supported. HTTP and HTTPS listeners: Not supported.
Forwarding policies	Associated with the default forwarding policy by default. Only default endpoint groups for TCP listeners can be associated with custom forwarding policies.	Can only be associated with custom forwarding policies.

Note

If your standard GA instance does not support adding virtual endpoint groups or configuring forwarding policies for TCP listeners, the instance version may not be supported. To use these features, contact your account manager to request an instance upgrade.

Prerequisites

You must have created a standard GA instance.
For subscription-based GA instances, you must have purchased and associated a basic bandwidth plan.
You have deployed an application to serve as a backend service for Global Accelerator. For more information about the backend service types that GA supports, see Endpoints.

Add a default endpoint group

Log on to the GA console.
On the Instances page, find the target GA instance and click Configure Listener in the Actions column.
On the Listeners tab, click Add Listener.

Note
If no listeners exist for the current Global Accelerator instance, skip this step.
On the Configure Listener & Protocol page, configure the listener protocol, port, and other parameters, and then click Next.

For more information about how to configure a listener, see Add and manage intelligent routing listeners.

On the Configure Endpoint Group page, configure the endpoint group.

Parameter	Description
Endpoint Group Name	Enter a name for the endpoint group.
Region	Select the region where the endpoint group is deployed. Note If the region where your endpoints are deployed is not supported by Global Accelerator, select the region that is nearest to your endpoints. Global Accelerator forwards access requests to the optimal node in the endpoint group.
Backend IP Version	Select the IP protocol that the GA instance uses to communicate with the backend service. IPv4: Uses only IPv4 addresses to communicate with the endpoint service. IPv6: Uses only IPv6 addresses to communicate with the endpoint service. IPv4/IPv6 (protocol affinity): The IP protocol that GA uses matches the protocol of the client request. If the client request uses IPv6, GA uses IPv6 to communicate with the endpoint service. If the client request uses IPv4, GA uses IPv4 to communicate with the endpoint service. Note Only standard GA instances that use the pay-as-you-go billing method and have listeners with a smart routing type support the configuration of backend IP protocols. Other types of GA instances do not support this configuration and use IPv4 by default. The backend IP address protocol feature is in invitational preview. To use this feature, contact your business manager. You cannot configure backend IP protocols if the endpoint group region is an Alibaba Cloud point of presence (POP). Call the ListAvailableBusiRegions operation to check whether a region is an Alibaba Cloud POP. You cannot configure OSS as a backend service if the backend IP protocol is set to IPv6 or IPv4/IPv6 (Protocol Affinity).
Endpoint Configuration	Endpoints are the destination hosts for client requests. Configure an endpoint based on the following information: Backend Service Type: You can select ECS, ALB, NLB, CLB, OSS, ENI, Custom private IP address, Alibaba Cloud Public IP, Custom public IP address, or Custom Domain Name. Note If your standard GA instance does not support backend service types such as ECS (VPC type), ALB, NLB, CLB (VPC type), ENI, or Custom Private IP Address, the instance version may be outdated. To use these features, contact your business manager to request an instance upgrade. To use GA to accelerate an unsupported Alibaba Cloud backend service type or an on-premises IDC service over a private connection, you can add an endpoint of the Custom Private IP Address type. Custom private IP addresses include, but are not limited to, the following standard private CIDR blocks: 10.0.0.0/8 100.64.0.0/10 172.16.0.0/12 192.168.0.0/16 To ensure high availability, select two or more vSwitches for the Backend Service. If you want to use public IP addresses as private IP addresses, these addresses are treated as private IP addresses when you use the custom private IP feature. If necessary, configure the required routes in the VPC. UDP listeners do not support ALB backend services. To ensure uninterrupted connectivity between the GA instance and backend services, you must configure access policies based on the network connectivity type of the backend service: Public connection: The access policy of the backend service, such as a security group or firewall, must allow traffic from the GA egress public IP address. Private connection: The access policy of the backend service, such as a security group or access control rule, must allow traffic from the vSwitch CIDR block where the backend service resides. You must also ensure that at least eight private IP addresses are available in the vSwitch CIDR block. The egress public IP address of the endpoints for each GA instance is unique and not shared with users of other GA instances. If you select ECS, ALB, NLB, CLB, OSS, ENI, or Custom Private IP Address as the backend service type and a service-linked role does not exist, the system automatically creates one. For more information, see AliyunServiceRoleForGaVpcEndpoint, AliyunServiceRoleForGaAlb, AliyunServiceRoleForGaOss, and AliyunServiceRoleForGaNlb. Backend Service: Enter the IP address, domain name, or instance ID of the backend server. Weight (Valid values: 0 to 255): Enter an integer from 0 to 255. Global Accelerator routes traffic to endpoints based on their configured weights. Warning If the weight of an endpoint is set to 0, Global Accelerator stops distributing traffic to that endpoint. Proceed with caution. You can click Add Endpoint to add multiple endpoints. You can add up to four endpoints. To add more endpoints, request a quota increase in the Quota Center. For more information, see Manage Global Accelerator quotas.
Preserve Client IP	Select whether to preserve client source IP addresses. If you enable this feature, the backend server can retrieve client source IP addresses. For more information, see Preserve client source IP addresses.
Backend Service Protocol	Select the protocol used by the backend service. Configure this parameter only when you set up an endpoint group for an HTTP or HTTPS listener. HTTP (default) HTTPS Note If the listener protocol is HTTP, the backend service uses HTTP by default and you cannot change the protocol. When the Backend Service Protocol is set to HTTPS, Global Accelerator (GA) supports TLSv1.0, TLSv1.1, TLSv1.2, and TLSv1.3 for connections to backend services, and automatically negotiates an available TLS version with the backend service. If your GA instance does not allow you to select the IP Version for backend service connections, the instance also does not support TLSv1.3 negotiation by default. To use this feature, contact your account manager to request an instance upgrade.
IP Version	Select the protocol version that Global Accelerator uses to connect to the backend service. This parameter applies only when Backend Service Protocol is set to HTTPS. HTTP/1.1 (default) HTTP/2 HTTP/2 significantly improves performance, reduces latency and network overhead, and enhances the overall access experience for backend HTTPS services. This applies to backend services that already support HTTP/2. If your backend service supports only HTTP/2, you must select HTTP/2. Note If your GA instance does not support selecting the IP Version for a backend service, this may be because the instance version is not supported. To use this feature, please contact your business manager to request an instance upgrade. If you select HTTP/2, the following limits apply: The WebSocket protocol is not supported. The Server Push feature of HTTP/2 is not supported. gRPC requests that are based on HTTP/2 cannot be accelerated.
Port Mapping	If the listener port differs from the endpoint port, you must configure port mapping. Listener Port: The port must be within the port range configured for the current listener. Endpoint Port: The port that the endpoint uses to provide services. Valid values: 1 to 65535. If the listener port is the same as the port that the endpoint uses to provide services, you do not need to configure port mapping. Global Accelerator automatically sends access requests to the endpoint on the listener port. For TCP and UDP listeners, you can click Add Port Mapping to add multiple port mappings. The Listener Port in each port mapping must be unique. You can add up to 30 port mappings. For HTTP and HTTPS listeners, you can add only one port mapping. Note If your standard GA instance does not support configuring Port Mapping for TCP or UDP listeners, it may be because the instance version does not support this feature. To use this feature, contact your business manager to apply for an instance upgrade. For TCP listeners: You cannot configure port mapping for virtual endpoint groups. If a virtual endpoint group already exists for the listener, you cannot configure port mapping for the default endpoint group. If port mapping is already configured for the default endpoint group, you cannot add a virtual endpoint group. After you configure port mapping, the following limits apply to subsequent listener changes: Listener protocol: You can switch only between HTTP and HTTPS. Switching between other protocols is not supported. Listener port: The modified listener port range must include all listener ports that have existing port mappings. For example, if the listener port range is 80–82 and is mapped to endpoint ports 100–102, the modified listener port range must include ports 80–82. You can change the range to 80–90, but you cannot narrow it to 80–81. For more information about how to use port mapping, see Use GA port mapping to improve application flexibility and security.
Traffic Distribution Ratio	Configure the percentage of traffic that is distributed to different endpoint groups. Valid values: 0 to 100. Note For the subscription billing method, only TCP and UDP listeners support traffic distribution. For the pay-as-you-go billing method, all listener types support traffic distribution. A value of 0 indicates that traffic is not forwarded to this endpoint group. A value of 100 indicates that all traffic is forwarded to this endpoint group. For more information about how to use traffic dialing, see How traffic dialing works and its use cases.
Health Check	Enable or disable health checks. When enabled, GA uses health checks to determine endpoint health status. For more information, see Enable and manage health checks. Note For a UDP listener, an endpoint must have a TCP, HTTP, or HTTPS service configured to support health checks. Otherwise, the endpoint is marked as unhealthy.
Health Check Protocol	Select the protocol for health checks. TCP, HTTP, and HTTPS are supported. TCP: sends SYN handshake packets to probe whether the server port is active. HTTP and HTTPS: send GET requests to simulate browser access and check the health of the backend service application.
Port	The probe port that the health check service uses to access the endpoint. Valid values: 1 to 65535.
Health Check Domain Name	The domain name for health checks. This feature is supported only by pay-as-you-go GA instances. Endpoint IP Address (default): Uses the IP address of the endpoint as the domain name for health checks. Custom Domain Name: Enter a specific domain name.
Health Check Interval	The interval at which health checks are performed. Unit: seconds. Valid values: 1 to 50. Unit: seconds. Default value: 2.
URI	The path for health checks. This parameter is available only when Health Check Protocol is set to HTTP or HTTPS. By default, GA sends a GET request to the default home page of the backend service application. If the page used for health checks is not the default home page, you must specify a path.
Healthy Threshold	The number of consecutive successful checks required to mark an endpoint as healthy, or consecutive failed checks to mark it as unhealthy. Valid values: 2 to 10. Default value: 3.
Tag	Set a tag for the endpoint group. Add a Key and Value to tag and categorize the endpoint group. For more information, see Manage tags.

Optional: Click + Add Endpoint Group and configure multiple endpoint groups as described in Step 5.

Note
For subscription GA instances, you can add more endpoint groups only for TCP and UDP listeners. For pay-as-you-go GA instances, you can add more endpoint groups for all types of listeners, including TCP, UDP, HTTP, and HTTPS.
In the Cross-border Acceleration Settings section, read the Compliance Commitments Regarding Cross-border Data Transfers and select Agree to the Preceding Compliance Agreement.

This step is required only if cross-border acceleration is not enabled for your GA instance and your service configuration involves cross-border acceleration between the Chinese mainland and other regions.
Click Next.
On the Configuration Review page, confirm the configuration and click Submit.

To modify the configuration, click Edit in the corresponding section to return to the previous page.

Add a virtual endpoint group

Log on to the GA console.
On the Instances page, find the target GA instance and click Configure Listener in the Actions column.
On the Listeners tab, find the target listener and click the number in the Virtual Endpoint Group column.
On the Endpoint Group tab, in the Virtual Endpoint Group section, click Add Virtual Endpoint Group.
On the Add Virtual Endpoint Group page, configure the virtual endpoint group and click Create.

For more information about the parameters, see Add a default endpoint group.

More operations

Actions	Description
Modify an endpoint group	On the Listeners tab, find the target listener, and then click the endpoint group ID or the number in the Default Endpoint Group column. On the Endpoint Group tab, find the target default or virtual endpoint group and click Edit in the Actions column. On the Modify Endpoint Group or Edit Virtual Endpoint Group page, modify the endpoint group name, endpoints, and other information, and then click Save. For more information about how to configure an endpoint group, see Add a default endpoint group. Warning We recommend that you switch the backend IP address protocol during off-peak hours. The switch may interrupt existing connections and affect your services.
Configure traffic dialing for an endpoint group	Set the percentage of traffic that is distributed to different endpoint groups. Note For the subscription billing method, only TCP and UDP listeners support traffic distribution. For the pay-as-you-go billing method, all listener types support traffic distribution. On the Listeners tab, find the target listener and click Edit in the Actions column. On the Configure Listener & Protocol page, click Next. On the Configure Endpoint Group page, find the target endpoint group, set the traffic dialing value, and then click Next. Valid values for traffic dialing: 0 to 100. Unit: %. On the Configuration Review page, confirm the configuration and click Submit.
Set the weight of an endpoint	The weight of an endpoint determines the proportion of traffic that Global Accelerator directs to each endpoint in an endpoint group. Global Accelerator calculates the sum of the weights of all endpoints in an endpoint group and then directs traffic to endpoints based on the ratio of each endpoint's weight to the total weight. For example, to distribute one-third of the traffic to an endpoint named EP1 and two-thirds of the traffic to an endpoint named EP2, you can set the weights of EP1 and EP2 to 1 and 2, respectively. To stop Global Accelerator from distributing traffic to an endpoint, set the weight of that endpoint to 0. On the Listeners tab, find the target listener, and then click the endpoint group ID or the number in the Default Endpoint Group or Virtual Endpoint Group column. On the Endpoint Group tab, find the endpoint group that contains the endpoint whose weight you want to set, and click Edit in the Actions column. In the Endpoint Configuration section of the Modify Endpoint Group or Edit Virtual Endpoint Group page, find the target endpoint, set a weight in the Weight (Valid values: 0 to 255) column, and then click Save. Valid values: 0 to 255.
View endpoint egress public IP addresses	On the Listeners tab, find the target listener and click View Endpoint Group in the Actions column. On the Endpoint Group tab, find the target endpoint group, and in the Endpoint Group IPs column, view the endpoint egress public IP addresses in the region of the endpoint group. Note The system assigns at least four endpoint egress public IP addresses to each endpoint group. The specific number of IP addresses also depends on the billing method of the instance: Pay-as-you-go: The number of IP addresses depends on the amount of service traffic. When service traffic changes, the CIDR blocks and IP addresses for endpoint egress traffic are elastically scaled. You can call API operations to query this information. For more information, see ListEndpointGroups and ListEndpointGroupIpAddressCidrBlocks. Subscription: The number of IP addresses depends on the instance specifications. When you upgrade or downgrade an instance, endpoint egress public IP addresses may be added or removed. You must manually confirm newly added public IP addresses for endpoint egress traffic before they can become active. You can confirm them in the console as prompted, or by calling the UpdateAcceleratorConfirm operation.
Delete an endpoint group	Deleting an endpoint group stops Global Accelerator from forwarding traffic to it. Warning If you delete the only endpoint group for a listener, the listener becomes unavailable. Proceed with caution. On the Listeners tab, find the target listener, and then click the endpoint group ID or the number in the Default Endpoint Group column. On the Endpoint Group tab, find the default or virtual endpoint group that you want to delete and click Delete in the Actions column. In the dialog box that appears, click OK.
Delete an endpoint	Deleting an endpoint stops Global Accelerator from forwarding traffic to it. You cannot delete the last remaining endpoint in an endpoint group. On the Listeners tab, find the target listener, and then click the endpoint group ID or the number in the Default Endpoint Group column. On the Endpoint Group tab, find the default or virtual endpoint group that contains the endpoint that you want to delete, and click Edit in the Actions column. On the Modify Endpoint Group page, in the Endpoint section, find the endpoint that you want to delete and click Delete in the Actions column. Then, click Save.

Tutorials

To learn how to configure multiple endpoint groups and traffic dialing, see the following topics:
- How traffic dialing works and its use cases
- Use GA traffic dialing for smooth traffic failover across regions
After creating an endpoint group for a listener, create a custom forwarding policy to forward matching requests to the associated default or virtual endpoint group, enabling a single GA instance to accelerate access to multiple destination endpoints.
For a tutorial on how to configure GA to connect to backend services by using HTTP/2, see Use HTTP/2 to connect to backend services.
For a tutorial on how to configure port mapping in GA, see Use GA port mapping to improve application flexibility and security.
For tutorials on how to retrieve client source IP addresses by using different GA listener protocols, see Preserve client source IP addresses.

API reference

CreateEndpointGroup: Creates an endpoint group for a standard GA instance.
CreateEndpointGroups: Creates multiple endpoint groups for a standard GA instance.
UpdateEndpointGroup: Modifies the configurations of an endpoint group for a standard GA instance.
DeleteEndpointGroup: Deletes an endpoint group for a standard GA instance.

Global Accelerator:Configure endpoint groups for intelligent routing